i am chasing a surging/dieng problem. We have tried/replaced everything we can think of. So we go to the computer. Try a chip without the Craig Moates adapter same thing. Then we start checking voltages from/to the ecm and check the b5/6 (I think) on the 24 pin connector. It is the sensor ground for Map/TPS?IAC and temp I think. With the key off it has a 0 ohm reading like it should. As soon as I turn the key on it jumps to 40-45 ohms. Can that be right? All grounds on the motor are good. I will be trying a new computer today. Any suggestions/and does my ground seem OK or not?


Thank YOU

Chris

 

The ohms reading is off as there is a voltage drop in the connection/wire. For circuits under power use a (mill-)volt scale to read the actual voltage drop.

RBob.

 

Thanks... I did that and replaced the computer. Still no dice. Do you think my program could be off in the chip to cause a bad idle surge/stall? What are the main tables I should look at?

Thanks

Chris

 

With the engine mods you have listed, yes I can believe some tweaking needs to be done. With a MAF setup the mmost important mechanical issue is air/vacuum leaks. Double & triple check for vacumm lines that are leaking. again for the bellows between the MAF & the TB. Correct PCV valve. Any unmetered air will throw off the calibration.

If you have removed MAF screens or did any gutting then the MAF scalar tables are off. Even if you didn't they probably need to be tweaked anyway.

Lots of info on dealing with MAF scalar tables in the archives, search & ask questions.

May also need to add more SA timing at idle. Lots of overlap on that cam. Increase idle RPM too.

RBob.