James Archer
Newbie
ordered module and thermal paste! Will be here Friday. Might even invest in tuner pro also if this doesn't fix anything.
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That may or may not cure your problem but, with proper data logging, you should be able to find it. Some links for TunerPro RT v5xxx etc...ordered module and thermal paste! Will be here Friday. Might even invest in tuner pro also if this doesn't fix anything.
More parts replacement without proper diagnosis.ordered module and thermal paste! Will be here Friday. Might even invest in tuner pro also if this doesn't fix anything.
More parts replacement without proper diagnosis.
But...you might get lucky.
Get the scan tool, use it. It's "possible" but CRAZY to try to fix a computer-controlled engine/trans/dashboard/ABS/Airbag system when you can't communicate with the computer that's making all the decisions, possibly with faulty data from a sensor or wire-harness problem.
Look at the data stream. "Codes" can be important. Data stream is CRUCIAL. Compare to values in the shop manual. What is the official procedure for the Code 42 you're seeing?
Check for codes, write 'em down--then clear the code(s) and see what comes back.
Did you ever fix the low oil pressure?
Did you ever verify that the fuel pump relay is working properly? Does the pump have a 2-second prime when the key is turned from "Off" to "Run"?
For the record...HOW OLD IS THE O2 SENSOR? Of all the sensors and actuators on a computer-controlled engine, the ONLY one I might replace "just because it's old" would be the O2 sensor. They get lazy as they age--they may still "work" but they don't react quickly like they should. You'd see this on the scan tool as a low number of "cross-counts".
Dear Old Dad bought a '98 Monte Carlo. The O2 sensor was old enough to buy liquor, but it only has about 35K miles on it. (It was original!) I changed it a week or two ago, I was getting 6 or 8 cross-counts; I'd rather see 20+.
There is only one.The O2 sensors ... ...O2 sensors
That's good news. The ECM can control the fuel pump via the fuel pump relay.The fuel pump does in fact prime for 2-3 second.
Connect a scan tool, look at commanded idle speed vs. actual idle speed. Perhaps the IAC or the IAC wire harness is defective.I have a similar problem, though nowhere near as bad. When in gear, idle speed, turning the wheel often causes the engine to die. This is a big problem when maneuvering my trailer around in the driveway or into a campsite. This week, I noticed a similar behavior when the A/C compressor kicks on when stopped at idle speed at a stop light. My truck is bone stock, and the only thing significant I've ever done to the engine is plugs/wires/cap/rotor. I also replaced the TBI gasket once a couple years ago trying to solve this problem but it didn't help. Any ideas?