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Discussion Starter · #1 ·
Hey guys
I have a 2004 bird with 74000km on it. Recent plugs, oil, clutch, coolant etc.

Noticed 3 days ago when it is idling or low speed maneuvers, it is sort of stuttering (or dancing around), it only fluctuates 50-100rpm but noticeable coasting in carparks in first.

Before I did the plugs, the boots were loose on the plug tops and it was running fine, so considering I fitted the plugs properly and fitted the spark plug leads properly, I doubt that's the cause.

Is there any other obvious cause? Injector cleaning any use?
Any sensors that get dirty?
Oil/coolant perfect.
I have run injector cleaner about 1000km ago. I use good fuel 95RON.

I'll make a video later if I can.

Cheers for help in advance.
 

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Make sure there are no air leaks, intake and exhaust. Make sure the air filter is seated properly, intake rubbers, exhaust gaskets etc.
Balance the throttle bodies. Type this phrase into search function above for more info.

Also, it is possible the FPR (fuel pressure regulator) is on the way out. They develop pinhole leaks that allow raw fuel to be pulled thru the vacuum line into the engine. Check the attached vacuum line, it should be bone dry.
 

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Discussion Starter · #3 ·
Make sure there are no air leaks, intake and exhaust. Make sure the air filter is seated properly, intake rubbers, exhaust gaskets etc.
Balance the throttle bodies. Type this phrase into search function above for more info.

Also, it is possible the FPR (fuel pressure regulator) is on the way out. They develop pinhole leaks that allow raw fuel to be pulled thru the vacuum line into the engine. Check the attached vacuum line, it should be bone dry.
Thanks - checked all that - I think it must be the FPR. Didn't pull the vacuum line as its late and I don't have much time.

I ordered a replacement FPR from Honda - let's try that. Its $126 AUD which is bad but not too bad. My V8 Volvo FPR cost $145 when I had it for a electronic bosch unit.

Cheers - I will park it up until the FPR comes. I dont want to have to do an oil change if the FPR is leaking fuel.
 

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Maybe adjusting the idle could be worth a try ? Just a thought ...?
On the FPR front just have a smell of your oil, if it smells of fuel that could be a giveaway sign that it is faulty.
 

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Discussion Starter · #5 ·
Maybe adjusting the idle could be worth a try ? Just a thought ...?
On the FPR front just have a smell of your oil, if it smells of fuel that could be a giveaway sign that it is faulty.
I gave it a whiff I can't really tell for sure. Smelt okay. Maybe thinner than usual? Hence my worry.

I can check the idle but it's not that as at low rpm it's not driving well. It's not just idle. After 3000rpm it seems fine.

I would love to balance my throttles but I won't have the tool and nobody in Darwin can be trusted with a bike. The mechanics are pure vandals. Last time I got tires they destroyed my wheels. I doubt they even have the tool here.
Might have to build the glass jar version. I'm too busy these days with family and balancing uni and work. When I was an undergrad I did all kinds of stuff like this.

Cheers for the help.
 

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G'day Exterminator,

I'm thinking ( :eek:.....oh no not again......) it will pay to confirm what plugs you screwed into the Bird before getting too involved in the problem and tearing into other systems.

Reasoning = it ran ok before the new plugs were installed.

So something isn't connected properly or the plugs are wrong/chinese copies or duds. Can you confirm you are using NGK plugs (they don't have to be Iridiums but they have to be the correct # for the 04BB). Maybe compare them side by side with the old plugs, looking for same shape and length etc etc(assuming the old plugs were the correct spec?).

The 04 should be much the same as my 05, so a K&N airfilter doesn't cause any issues like it does on the carby model.

Plug caps should have zipped/ratcheted their way securely onto the plug so the originals shouldn't have been loose (= difficult to prize off). Recheck that the plugs are fully seated with the crush rings nicely torqued but not over tightened. I use my wright wrist as a torque meter after hundreds of years of changing plugs I get them just right, not too tight, but they never come loose either. Those crush rings need to be seated, released, then re-seated to settle properly.

The FPR is a good thing to change anyway, so it's not money wasted as if one goes and you don't realize fast enough it can take down one of the main bearings and destroy the motor due to fuel-oil dilution. I changed my FPR last year as part of a 16yr preventative maintenance check during travel restrictions (treated tank rust, changed coolant, oil, plugs, brake fluids and FPR and tested fuel pump output).

At 70k kms you may have an alternator on the way out (Mine stranded me at 73k kms) so check the charging system and load test the battery (easy to do but check cranking volts when engine cold/rested 12hrs - you should see >9.5v while cold cranking, then on start up, volts should be about 13v, then at 1500-2k rpm volts should be 14-14.5). If that's all ok, then the alternator and Reg rect and battery are fine....... I needed a coil rewind that time, but my R/R was undamaged. A new battery is all I replace, once the load test registers <9.5v cold cranking.

As a general rule, in this type of circumstance, go back over everything you worked on...... just in case something was forgotten or not put back on just right...... I tripple check my own work.... me being the weakest link in the BB's armour ;):LOL:
 

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Discussion Starter · #7 ·
G'day Exterminator,

I'm thinking ( :eek:.....oh no not again......) it will pay to confirm what plugs you screwed into the Bird before getting too involved in the problem and tearing into other systems.

Reasoning = it ran ok before the new plugs were installed.

So something isn't connected properly or the plugs are wrong/chinese copies or duds. Can you confirm you are using NGK plugs (they don't have to be Iridiums but they have to be the correct # for the 04BB). Maybe compare them side by side with the old plugs, looking for same shape and length etc etc(assuming the old plugs were the correct spec?).

The 04 should be much the same as my 05, so a K&N airfilter doesn't cause any issues like it does on the carby model.

Plug caps should have zipped/ratcheted their way securely onto the plug so the originals shouldn't have been loose (= difficult to prize off). Recheck that the plugs are fully seated with the crush rings nicely torqued but not over tightened. I use my wright wrist as a torque meter after hundreds of years of changing plugs I get them just right, not too tight, but they never come loose either. Those crush rings need to be seated, released, then re-seated to settle properly.

The FPR is a good thing to change anyway, so it's not money wasted as if one goes and you don't realize fast enough it can take down one of the main bearings and destroy the motor due to fuel-oil dilution. I changed my FPR last year as part of a 16yr preventative maintenance check during travel restrictions (treated tank rust, changed coolant, oil, plugs, brake fluids and FPR and tested fuel pump output).

At 70k kms you may have an alternator on the way out (Mine stranded me at 73k kms) so check the charging system and load test the battery (easy to do but check cranking volts when engine cold/rested 12hrs - you should see >9.5v while cold cranking, then on start up, volts should be about 13v, then at 1500-2k rpm volts should be 14-14.5). If that's all ok, then the alternator and Reg rect and battery are fine....... I needed a coil rewind that time, but my R/R was undamaged. A new battery is all I replace, once the load test registers <9.5v cold cranking.

As a general rule, in this type of circumstance, go back over everything you worked on...... just in case something was forgotten or not put back on just right...... I tripple check my own work.... me being the weakest link in the BB's armour ;):LOL:
Thanks for the thorough reply Dave.
I appreciate it.

I had no issues after the new plugs although about 500km later the problem came up. They were NGK Iridium from Repco so doubt they were fake although eBay always has fakes that's for sure.

I think your right about the FPR. I just received it today and will throw it in later. I noticed the fuel hose is a bit dry and cracked. Good to replace.
Also the injectors will get new seals and a clean, I ordered a kit from a place in the UK specifically for Keihin injectors.
I gave a new fuel pump and filter as well as I thought its cheap insurance and the tank is a bit gross inside. I probably won't bother sealing it but I might if it proves to be really dirty.

I am respraying the tank black soon so doing all these jobs is worthwhile for peace of mind. I'd like the bike to last whilst I am at uni for a few years. I was about to buy a Ducati 848 before I got this though so you never know. If another comes up in Darwin I might have to grab it.

I like my machines to run like new so I tend to go a bit overboard rebuilding everything.
 

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Cheers Exterminator,

There is a section in the workshop manual in the reference section of this forum..... (download the 99-02 manual as it covers the later FI Birds). There are plenty of great tips to problem solve..... and even ideas i never knew about - who would've though a manual could be so useful...... but it is ;)

I suppose rust coud be blocking the fuel filter/pump so.......

It's a DIY job to test the fuel pump flow rate (I didn't do a pressure test as I was changing the FPR anyway).... all that's needed is to plug the tank return (so it doesn't leak fuel everywhere) and run the motor for 10secs while catching the return flow in a container. It should pump 220mls of fuel into a container using the return hose/extension tube so that means the fuel pump is fine - mine was 130k kms old and passed - Honda quoted $800 (+nil stock) for a replacement fuel pump (ouch). I replaced the fuel filter as it was 16yo.... $100 from Wemoto (nil stock Honda). Others were smarter than me and bought K&N equivalents for a lot less.... oh well, it was in my hands in 3 days.

Check that tank for rust - it hides out of sight up under the roof of the tank so can only be seen by removing the fuel pump. If it's there (from long term storage with a less than a full fuel tank..... don't ask how I know this :( ), it will need acid cleaning with Hydrochloric Acid ($6 Bunnings Pool Shoppe) and then sealing with a good treatment like KBS.

Don't bother with their stage 1 wash cycle...... the HCL is the best way to remove the rust (in seconds). Just be careful working with acid ;). Add a small amount of acid (say 50-100cc) to a 200-400cc puddle of water in the tank (filler hole plugged tightly with a laundry tub plug) and watch closely as you swish it around the rusty areas. Stop and flush with water when done, and repeat if needed. Note, don't add water to acid as it spits in your eyes....

Use a torch or a converted work lamp with a skinny bulb that will fit inside the tank so you can see how well it's worked.

Rust disappears in seconds and the tank can be flushed out with water using the garden hose, dried with a hair drier, then with the KBS treatment, stage 2 coated with a zinc film which means it won't rust so you don't need to rush into the final sealer coat for a day or so. I took all the precautions and organized myself, and found the process very easy.

However, there is a vent tube from the filler neck down to the tank base which is the overflow for fuel spills. Check it is not eaten away, and make sure you plug the small breather hole with something like a match stick so the final sealer coat doesn't block it and cause a vacuum to build up while riding. If this tube system is badly corroded, it could be game over for the tank. Mine had been eaten into but was still viable, and works fine now it's coated and sealed.

Rust treatment should be done before you paint the outside of the tank (obviously). My tank was pristine, so I had to make sure I didn't spill any HCL....... I didn't :D.

I'm so happy with the sealer treatment...... it's permanent and no rust will ever form again.... (y). It's a process that requires two plates to seal the fuel sender hole and the fuel pump hole (using the old gaskets), with the filler neck plugged with a plastic tub bung........ and of course you will need new gaskets for the pump and fuel level sender. I took 3 days to leisurely and safely do the job. There are U-tube video's for similar treatments you can use for planning and mental preparation.

I doubt the injectors need kitting, but you are on the spot, so it's your call, but mine are untouched at 16yrs and still fine..... all I do is pour 70-90mm of Valvoline Injector Cleaner in with a tank full of 95octane for three tanks before I do an oil change and mine runs sweet as. I have my own fluid manometers, so I balance the throttle bodies when I feel they are out (vibes, or lumpy idle, poor economy). When I do them, I spray some Upper Cylinder Cleaner (I use Subaru's UCL) into the small holes lurking under the airbox trumpets as these drain down into the cylinder intakes and can carbon up and affect the throttle body synch. Air leaks are the critical thing with TB synchro..... must get it right or it's a :poop: outcome. I see others have a very nice modern synchro tool vs my old fashioned set........

Check that vacuum hose from the FPR to the throttle body...... it must be dry, otherwise it's leaking fuel into no 2 or 3 and therefore down past the rings and into the oil. The poor running may be the plugs sooting up - whip them out and inspect to confirm.

Good luck...... with the bike and the study.

There you go..... that's a heap of work to do....... unfortunately it won't earn any assignment points towards your Degree....... BTW, I have a BSc degree.... but I always say that stands for Bloody Silly C.....err not here Davo, it's a family forum....... :devilish:
 

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Discussion Starter · #9 ·
Cheers Exterminator,

There is a section in the workshop manual in the reference section of this forum..... (download the 99-02 manual as it covers the later FI Birds). There are plenty of great tips to problem solve..... and even ideas i never knew about - who would've though a manual could be so useful...... but it is ;)

I suppose rust coud be blocking the fuel filter/pump so.......

It's a DIY job to test the fuel pump flow rate (I didn't do a pressure test as I was changing the FPR anyway).... all that's needed is to plug the tank return (so it doesn't leak fuel everywhere) and run the motor for 10secs while catching the return flow in a container. It should pump 220mls of fuel into a container using the return hose/extension tube so that means the fuel pump is fine - mine was 130k kms old and passed - Honda quoted $800 (+nil stock) for a replacement fuel pump (ouch). I replaced the fuel filter as it was 16yo.... $100 from Wemoto (nil stock Honda). Others were smarter than me and bought K&N equivalents for a lot less.... oh well, it was in my hands in 3 days.

Check that tank for rust - it hides out of sight up under the roof of the tank so can only be seen by removing the fuel pump. If it's there (from long term storage with a less than a full fuel tank..... don't ask how I know this :( ), it will need acid cleaning with Hydrochloric Acid ($6 Bunnings Pool Shoppe) and then sealing with a good treatment like KBS.

Don't bother with their stage 1 wash cycle...... the HCL is the best way to remove the rust (in seconds). Just be careful working with acid ;). Add a small amount of acid (say 50-100cc) to a 200-400cc puddle of water in the tank (filler hole plugged tightly with a laundry tub plug) and watch closely as you swish it around the rusty areas. Stop and flush with water when done, and repeat if needed. Note, don't add water to acid as it spits in your eyes....

Use a torch or a converted work lamp with a skinny bulb that will fit inside the tank so you can see how well it's worked.

Rust disappears in seconds and the tank can be flushed out with water using the garden hose, dried with a hair drier, then with the KBS treatment, stage 2 coated with a zinc film which means it won't rust so you don't need to rush into the final sealer coat for a day or so. I took all the precautions and organized myself, and found the process very easy.

However, there is a vent tube from the filler neck down to the tank base which is the overflow for fuel spills. Check it is not eaten away, and make sure you plug the small breather hole with something like a match stick so the final sealer coat doesn't block it and cause a vacuum to build up while riding. If this tube system is badly corroded, it could be game over for the tank. Mine had been eaten into but was still viable, and works fine now it's coated and sealed.

Rust treatment should be done before you paint the outside of the tank (obviously). My tank was pristine, so I had to make sure I didn't spill any HCL....... I didn't :D.

I'm so happy with the sealer treatment...... it's permanent and no rust will ever form again.... (y). It's a process that requires two plates to seal the fuel sender hole and the fuel pump hole (using the old gaskets), with the filler neck plugged with a plastic tub bung........ and of course you will need new gaskets for the pump and fuel level sender. I took 3 days to leisurely and safely do the job. There are U-tube video's for similar treatments you can use for planning and mental preparation.

I doubt the injectors need kitting, but you are on the spot, so it's your call, but mine are untouched at 16yrs and still fine..... all I do is pour 70-90mm of Valvoline Injector Cleaner in with a tank full of 95octane for three tanks before I do an oil change and mine runs sweet as. I have my own fluid manometers, so I balance the throttle bodies when I feel they are out (vibes, or lumpy idle, poor economy). When I do them, I spray some Upper Cylinder Cleaner (I use Subaru's UCL) into the small holes lurking under the airbox trumpets as these drain down into the cylinder intakes and can carbon up and affect the throttle body synch. Air leaks are the critical thing with TB synchro..... must get it right or it's a :poop: outcome. I see others have a very nice modern synchro tool vs my old fashioned set........

Check that vacuum hose from the FPR to the throttle body...... it must be dry, otherwise it's leaking fuel into no 2 or 3 and therefore down past the rings and into the oil. The poor running may be the plugs sooting up - whip them out and inspect to confirm.

Good luck...... with the bike and the study.

There you go..... that's a heap of work to do....... unfortunately it won't earn any assignment points towards your Degree....... BTW, I have a BSc degree.... but I always say that stands for Bloody Silly C.....err not here Davo, it's a family forum....... :devilish:
Cheers Exterminator,

There is a section in the workshop manual in the reference section of this forum..... (download the 99-02 manual as it covers the later FI Birds). There are plenty of great tips to problem solve..... and even ideas i never knew about - who would've though a manual could be so useful...... but it is ;)

I suppose rust coud be blocking the fuel filter/pump so.......

It's a DIY job to test the fuel pump flow rate (I didn't do a pressure test as I was changing the FPR anyway).... all that's needed is to plug the tank return (so it doesn't leak fuel everywhere) and run the motor for 10secs while catching the return flow in a container. It should pump 220mls of fuel into a container using the return hose/extension tube so that means the fuel pump is fine - mine was 130k kms old and passed - Honda quoted $800 (+nil stock) for a replacement fuel pump (ouch). I replaced the fuel filter as it was 16yo.... $100 from Wemoto (nil stock Honda). Others were smarter than me and bought K&N equivalents for a lot less.... oh well, it was in my hands in 3 days.

Check that tank for rust - it hides out of sight up under the roof of the tank so can only be seen by removing the fuel pump. If it's there (from long term storage with a less than a full fuel tank..... don't ask how I know this :( ), it will need acid cleaning with Hydrochloric Acid ($6 Bunnings Pool Shoppe) and then sealing with a good treatment like KBS.

Don't bother with their stage 1 wash cycle...... the HCL is the best way to remove the rust (in seconds). Just be careful working with acid ;). Add a small amount of acid (say 50-100cc) to a 200-400cc puddle of water in the tank (filler hole plugged tightly with a laundry tub plug) and watch closely as you swish it around the rusty areas. Stop and flush with water when done, and repeat if needed. Note, don't add water to acid as it spits in your eyes....

Use a torch or a converted work lamp with a skinny bulb that will fit inside the tank so you can see how well it's worked.

Rust disappears in seconds and the tank can be flushed out with water using the garden hose, dried with a hair drier, then with the KBS treatment, stage 2 coated with a zinc film which means it won't rust so you don't need to rush into the final sealer coat for a day or so. I took all the precautions and organized myself, and found the process very easy.

However, there is a vent tube from the filler neck down to the tank base which is the overflow for fuel spills. Check it is not eaten away, and make sure you plug the small breather hole with something like a match stick so the final sealer coat doesn't block it and cause a vacuum to build up while riding. If this tube system is badly corroded, it could be game over for the tank. Mine had been eaten into but was still viable, and works fine now it's coated and sealed.

Rust treatment should be done before you paint the outside of the tank (obviously). My tank was pristine, so I had to make sure I didn't spill any HCL....... I didn't :D.

I'm so happy with the sealer treatment...... it's permanent and no rust will ever form again.... (y). It's a process that requires two plates to seal the fuel sender hole and the fuel pump hole (using the old gaskets), with the filler neck plugged with a plastic tub bung........ and of course you will need new gaskets for the pump and fuel level sender. I took 3 days to leisurely and safely do the job. There are U-tube video's for similar treatments you can use for planning and mental preparation.

I doubt the injectors need kitting, but you are on the spot, so it's your call, but mine are untouched at 16yrs and still fine..... all I do is pour 70-90mm of Valvoline Injector Cleaner in with a tank full of 95octane for three tanks before I do an oil change and mine runs sweet as. I have my own fluid manometers, so I balance the throttle bodies when I feel they are out (vibes, or lumpy idle, poor economy). When I do them, I spray some Upper Cylinder Cleaner (I use Subaru's UCL) into the small holes lurking under the airbox trumpets as these drain down into the cylinder intakes and can carbon up and affect the throttle body synch. Air leaks are the critical thing with TB synchro..... must get it right or it's a :poop: outcome. I see others have a very nice modern synchro tool vs my old fashioned set........

Check that vacuum hose from the FPR to the throttle body...... it must be dry, otherwise it's leaking fuel into no 2 or 3 and therefore down past the rings and into the oil. The poor running may be the plugs sooting up - whip them out and inspect to confirm.

Good luck...... with the bike and the study.

There you go..... that's a heap of work to do....... unfortunately it won't earn any assignment points towards your Degree....... BTW, I have a BSc degree.... but I always say that stands for Bloody Silly C.....err not here Davo, it's a family forum....... :devilish:
So no luck with the FPR. It possibly made it minutely smoother but I still have the idle/low RPM stutter, especially around parking lots, etc.

Noticed my temp sensor reading as high as 110 but the fan didn't kick on, and it was at the same spot on my regular commute where it is usually 98-99c or so. I am wondering if the engine temp sensor affects the EFI? Maybe my sensor is going cactus.
Since replacing my thermostat, my bike shouldn't be getting to 110 on a regular ride without stopping.

I have bought a KBS sealer kit in Darwin locally which was a lifesaver as I didn't have to wait 3+ weeks for postage.

I'm just waiting on my fuel pump/filter to arrive, then its all go on refreshing the tank.

Hoping that injector cleaning will sort my EFI issues.
 

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:unsure:....... hmmmm, 110C with no fan on........ hmmmm..... something is wrong.

Your fan should cut in around 100C (my 05 does)..... and, as the engine warms up (stationary garage test, hold rpms at say 1500) you should see the temp hit 85C then suddenly drop back down to 79C and then start climbing again until the fan cuts in at 100-103C. That dip in temp at 85C is the thermostat opening fully....... so if this isn't happening, you may have several issues, like old coolant, or a stuck thermostat, or a wiring/electrical issue preventing the temp sensor triggering the fan.

If the coolant has been neglected (usually 2-3yrs life depending on brand used) there could be sediment/corrosion, or a leak into the cyl head (check the coolant level is stable - has it lost volume when cold in both the overflow tank and the radiator?). If that's not an issue, check the age of the radiator cap...... even a new cheapie $22 MCS cap (I bought one and it works fine) is better than relying on a 10yr old $54 Honda cap that may no longer be sealing or allowing fluid to pass at the spec pressures.

Water pump should be ok at these kms, but if coolant has been neglected over the years it too may have been leaking (mine 1st leaked at around 90k kms.... i didn't spot it as the foam inside the fairing soaked it up, so no drip on the floor - but i did spot the catch tank level slowly reducing over time).

A severely out of balance engine may be the underlying issue, but I've never let mine get that bad so I don't know the symptoms as I have been balancing mine at regular intervals. (the workshop manual on the forum reference page should have some trouble shooting info).

Did you do the DIY fuel pump flow test?...... that will quickly confirm if the pump is underperforming (see the workshop manual), which would mean the fuel rail doesn't have enough pressure to make the injectors work properly.

Good luck, and keep posting how you go. All info helps focus our grey matter....... (y)
 

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Maybe some of the more knowledgeable (and better looking) members are possibly leaning towards cracked vacuum hoses or wiring faults....... there is a way of decoding the ECU by counting the flashes and matching the codes..... it's on here somewhere, but maybe someone can easily post it up.
 

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Discussion Starter · #12 ·
Thanks Dave.
I've flushed and changed the coolant. New thermostat (Honda Australia) and new rad cap (tried back and forth between two caps).

I noticed my delkevic exhaust has a little hole where there is a possible exhaust leak near the entrance into the muffler. I think that I possibly need to loosen and refit the cans and block these (drain?) Holes.

I got the fuel filter today🔥still waiting on pump and 2pack paint to overhaul my tank. I got the kbs tank sealer already.

Hopefully can smooth the bike out soon.
 

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Cheers Ext.....

Just had a rare thoughtie ....... can you check your plug leads with a multimeter? Maybe the resistance has changed on one or more leads-plug caps? I think they should all be around 5k Ohms, if you put a probe on the open wire end and the other up inside the cap where the sparkplug connects...... you never know, resistance can go either way with age, but the ECU needs the resistance to be in spec.
 
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