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Re: staggers & stutters redux redux Posted by Justin VanAbrahams [Email]  (#32) [Profile/Gallery]
(more from Justin VanAbrahams) on Wed, 10 Feb 2016 20:20:17
In Reply to: Re: staggers & stutters redux redux, Jeyi, Wed, 10 Feb 2016 18:33:03 Members do not see ads below this line. - Help Keep This Site Online - Signup |
ECU is where I'd look. It sounds like there is a problem when the TPS shows no throttle but revs are still up. In that scenario, the ECU should cut fuel until revs drop to a predetermined amount (like, approaching idle) at which point it goes into idle mode. It sounds like that's not happening, purely on the basis that during decal, the engine should effectively be doing nothing. This would be fairly easy to monitor, with a small LED connected to 12v and the fuel injector pulse signal (ground). If you see the LED pulsing when your foot is off the gas but the engine is above, say, 1500rpm you know the fuel cut isn't working.
... on that subject, have you verified the TPS is working? The 2.1l motors have a potentiometer versus a simple switch. I don't know the test offhand, but it's in the Bentley.
Related, the poor fuel economy could be from a wacky TPS, AMM, OR the ECU not doing what it should - thinking it needs more fuel to compensate for an incorrect high air mass rate OR from an incorrect load (TPS) signal.
I am a little baffled by the indy's comments on the ECT and O2 sensor, only because those are trim devices and not primary input. I don't really see how either part could totally eff up driving. Maybe he knows something I don't.
Finally, have you done any of the wiring pinout tests from the Bentley? They are annoying and time consuming, but not difficult to do. You just back probe the connector to be sure volts & ground are where they should be.
.... Related, have you fully inspected the wiring harness to ensure it's not wrecked? I once bought an '87 that had all sorts of wacky drivability issues, and it turned out the wiring harness had fallen from the wire tie on the head and gotten ground up on the water pump pulley. Oopsie.
posted by 12.195.130...
, Wed, 10 Feb 2016 16:14:26, Wed, 10 Feb 2016 20:20:17 <-- Viewing This Message, Wed, 10 Feb 2016 20:24:33
, Thu, 11 Feb 2016 15:53:50, Tue, 9 Feb 2016 18:31:21
, Tue, 9 Feb 2016 18:29:25
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