okay so im working on a 1988 camaro with a TPI.at first the at first the car wouldnt start but after i replaced the distributor, wires, ignition coil and spark plugs i got it to run. now i have a code 34 as the title states and it idles a little funny but also bogs down under throttle. ive replaced both relays, swapped out maf sensors, replaced the oil pressure switch (wiring diagram shows power runs through the switch in order to reach power and burn off relays) ive measured 12 volts going to the maf, but i wasnt getting voltage to the signal wire( 5 volt reference). i probed the signal wire and backprobed the connections to the ecm and found i had good continuity. so this is where it gets funny. i swapped out ECMs from another camaro i have and voila it was fixed (or so i thought) the issue with running that ECM is that its tuned to run on the other camaro which has a crate engine installed with different engine specs but i was still able to get it to rev and no more bogging. i ordered a new ECM and swapped chips and im back to square 1 doing the same thing it was doing on the other ECM. i measured voltage coming out and i was getting .5 volts at idle so the ECM is recieving a signal but the car still bogs. ive checked for vaccum leaks and nothing. im running out of ideas here. if anyone has any suggestions it would be greatly appreciated.

 

http://web.archive.org/web/201801251...vythunder.com/
if it turns out to be a maf get used bosch or new Delphi
​​​​​. What’s idle grams per second?

 

.55 vdc is 6.38 gps just a FYI

 

4-7 gps is spec although I’ve seen 9 a lot on stock and modified engines.
https://www.thirdgen.org/forums/tpi/...l#&gid=1&pid=3

 

the maf sensor I swapped it for was Bosch. Unfortunately I don’t have a scanner that will tell me that.

 

Anyone?

 

The signal to the ecm could be high in resistance but to datalog or use a scanner to see what idle gps are.
or ohm the wire and check for connector terminal corrosion.

 

Is there a spec it’s supposed to be between?

 

https://www.inchcalculator.com/wire-...ce-calculator/

 

On early computer cars often a system will throw a code in area that is not really the issue because there is a mechanical part failure and the system to basic to tell you the true problem. So a common cause of a code 34 is actually leaking injector nozzles and failing injectors. Test the injector coils and report the readings. Then connect a fuel pressure gauge note and report the pressure reading while running. Then when you turn the car off leave the gauge connected and note how long it takes for it to bleed down to zero. If bleeds down to zero very fast the injectors are leaking.

I truly think this is a mechanical issue in the fuel system.

 

I was also thinking fuel pump. Whenever I would throttle it and it would bog i had the fuel pressure gauge hooked up and you could see it fluctuate pretty bad. But I will definitely try that !

 

Swapped out the fuel pump and still doing the same thing

 

So I’ve ohmed out the injectors and those tested fine. I’ve swapped fuel pump and FPR and still nothing.