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Discussion Starter #1
Hello,

last summer i had a engine failure. So i fitted a used fi engine with all the sensors and throttle bodies from the new engine. But kept the ecu from the old engine.

Since then i could not get it to idle properly. It takes long time to start, when doing a cold start it first idels arround 1000rpm and after some seconds it starts to fast idle at 2500rpm. Normally it should fast idle directly after starting.

Then when warmed up i will not idle at all. I idles for some seconds and then stalls immediately just like when you kill the ignition. When driving with just very little throttle it also sometimes cuts out.

For me it feels like the tps sensor is not set up correct. So the ecu puts the overrun fuel cut in when it should not.
The fi lapms show no error code.
So far i have checked the fast idle wax unit, the linkage of it and did syncronize the throttels. But that did not help.

Can you adjust the tps?

Regards

Christoph
 

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Greetings masterslamma,

I would check for vacuum leaks around the throttle body.
I had idle change due to leaking clamps on throttle body tubes. Spray carb cleaner around fittings to see if any changes.
Only way to zero the TPS is to have a power commander.
Recon you know how to adjust idle with the knob on left side below?
You can check the TPS with and ohm meter to see if it has a liner change as it opens. If it jumps around then its bad. Only can be replaced by changing the throttle body and recon u have a spare.

STex, out
 

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Discussion Starter #3
Hi.

I checked the tps with a voltmeter and it showed 0.54 Volts at closed throttle.

I the thougt i test 0.4 Volts and 0.7 Volts.

With 0.4 the engine startet on the first crank and ran perfekt. Did a testdrive and i now drives again like it should.

I guess if you change the tps but keep your old ecu the tps will not be adjustet right in the ecu.
You can also not adjust it with a power commander, because you only can adjust the tps to the power commander.

Regards
 

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I think MY 1999 and 2000 have different ecu compared to newer birds. Don't know what the differences are though.
 

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Discussion Starter #5
Yes thats right. A friend has a newer one and his ecu has a different code.

I will measure the output voltage pf my old throttle body and then adjust the new one to the same voltage.
 
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