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95' E420
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Discussion Starter #1
Hi,

Does anyone know the nominal values to look for on ECT, AIT, O2 when testing them? Could a faulty MAF also be tested as well to find out if its working properly or does it pretty much just die out. I have no CEL on, but I am trying to find out if these are OK.

Thkz,

DH
 

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O2 you can see it oscilate with a hand held O-scope.

Are you having driveability problems? What codes are you getting?
 

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95' E420
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23 Posts
Discussion Starter #3
Currently I am not getting a CEL light, I still haven't probed for any stored DTC's in the DM, DI, BM and LH-SFI modules. So far the car idles a little rough at times but what concerns me most is that it lags when you floor it, and will no shift into 3rd at 5500 rpm it chokes until you let go of the pedal a bit, then it shifts..hard..and my m.p.g. went down the drain..bout 9 or 10 to a gal..I need to keep it under 2000 rpm or the gas tank will evaporate in a heartbeat..

From visual inspection I can tell the IAT is shot, but I highly doubt that it will have such a high impact on the vehicles performance..The car has 133K miles so the MAF might be on its last leg..

I just need to pinpoint the source(s) of this problem before I go all-out and buy parts at AZ.

Any thoughts?

DH
 

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Have the upper and lower engine harnesses been replaced?

Rough runnings... what are the condition of the distributor caps and rotors?

At that mileage- I would think the MAF is probably good. If it has a ETA, the harness and actuator can be part of the problem.


I would clear the codes and then drive it and read them.
 

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95' E420
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Discussion Starter #5
I would have to go over the wiring harness. I don't think it has been replaced, but I am not getting any 'Limp Home' codes. The only codes I was able to pull where 25 and 26. The KS and up-shift delay.. I don't believe it could be the ETA since I am not getting any ASR codes or lights as well, but I don't know how I could go about and test it without having to remove the MAF and dig into the manifold..?

I will did in deeper for any vacuum leaks in the black intake hoses towards the back of the manifold..I just detected some sweat around the 'Y' hose and a little grime/dirt around it..not sure if it was transfer from a previous valve cover gasket leak though..
 
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