MathalomuleM31

So I bought a 1994 V6 Camaro about a year ago. she was a bit of a wreck... long story short i worked on her but then we hit a roadblock. She kept missfiring randomly and could not for the life of us figure it out. But anyway, i got sick of it and swapped out the V6 for a nice LT1 from a 96 Z28 Put her in, got a harness and PCM from a 95 Z28. (Automatic Transmission from a 95 i believe) Took forever but finally got her finished. Everything dandy except for a knock sensor code and two transmission codes in the check engine light. but spite those she ran great. had no problems for about a month and a half. Then all the sudden she started doing what i said in the title. Everytime i make a right curve the engine shakes and grogges down and backfires when i try to accelerate after the turn. After she poppes a few she revs up and runs like normal. She WILL NOT do it on left turns and ive tried to make her but she wont. I rulled out a transmission problem because durring a turn i tried to pop her into neutral and shel still grogg. even if i stop and put her in park she will still grogg, and after a few presses on the gas she backfire and rev like normal.

Im clueless on this matter, any help would be GREATLY appreciated. a few other things to consider... When i got her back with her LT1 in she got 7 MPG so my mechanic suggested a tune. and it worked great, but still iffy... i get round 11 now. better but still kinda bad... (I was thinking that bad MPG may be linked to the grogging porblem?) It started grogging about 2 weeks after i got the tune.
My mechanic found that the mass air flow meter was a bit off and replaced it and the connector for it. But no luck.
He also tried looking at the knock sensor. He bypassed it to see if the code would go off but it didnt, and the car still grogged spite bypassing the knock sensor. I think maybe the knock sensor problem lies within the knock sensor module itself within the PCM.

Also, she wont grogg if i stop completely and turn right (like a redlight or stop sign), or turn at a really slow speed. Shel only do it on a right turn somewhat sharp like 15MPH or higher.

This is my first car and i love her I just wish we could get this right... Any input would be great thanks!

timnfxr

Check the plug wires to make sure they're in good shape and not against the header.

You can also check the fuel pressure to rule out marginal pressure. Tape the gauge to the windshield to see what happens when the problem occurs.

MathalomuleM31

The plug wires are good, I got a new connector on there and it's no where near moving or hot parts so I'm good with that. Okay might try that. I just now got back from the shop showing the problem to my mechanic again. And we checked the air flow meter that we just replaced and it's readings are off, it's giving it too much gas. So I guess that's where my problem is? He's going to replace it on Tuesday to see if that solves it. If not could it be my tune throwing off the mass air flow meter?

timnfxr

So its running rich. What condition are your O2 sensors in? Is their wire routing in the clear? I'm not sure if or how the MAF sensor would cause your symtoms when you're making right turns. Is the MAF connection good, and is there a little slack in that cable?

Injuneer

The 96 knock sensor (100Kohms) is not compatible with the 95 PCM (looking for a 4.4Kohm sensor). "Bypassing" if that means jumping the single harness wire to the block, or disconnecting the wire will not eliminate the code.

Could be be a bit clearer on what "grogging" is.... 50 years and I never heard that one. Do you mean "bogging"?

Did you check the fuel pressure as suggested? Almost sounds like it's starving for fuel in the right turns.

MathalomuleM31

The wire routing for the MAF connector for sure is in the clear. The rest of the harness im not sure, i believe he checked it but im not certain.

He checked the readings right from the pins in the connector as it was hooked up to the MAF meter and its readings were off. As of right now I suppose the MAF meter would be the best place to look since that is under warranty (free service ) and it would explain poor gas mileage. But yeah i have to clue why right turns are the cause... If switching the MAF meter out doesn't work were definetly gonna check out the harness for sure and possibly the PCM.

MathalomuleM31

I was reading up on that and I wasnt certain about the knock sensor thank you. So getting a knock sensor for a 95 LT1 will solve the problem? Or do I need to replace the knock module in the PCM with one from a 96? Or does the whole PCM have to be replaced with a 96 PCM? Yes bogging would be the word, Hey you hear new ones every day
I didnt check the fuel pressure yet. Thatll next on my list of diagnostics after we get this MAF meter figured out.

lt11997

Drive it with a fuel pressure guage on it. I had the same symptoms on a customers car with a escort and it ended up being the fuel pump strainer.

MathalomuleM31

Hmm... okay ill suggest it to my mechanic thanks!

Injuneer

Yes, you need to use a knock sensor from a 93-95 LT1.

If the MAF is not accurate (did he measure signal output using a digital frequency meter?) the O2 sensors should pick up the lean or rich condition and the PCM should adjust the long term fuel trims to correct the condition. If the required correction approaches the limits of the LTFT's the PCM should setcodes for rich or lean.

MathalomuleM31

Okay noted thank you.

Yes he did measure the signal with a digital frequency meter, and apparently the signal is off to the point that its allowing too much gas and not enough air (burning rich).
And also, I have shorty headers on and i know that will throw off O2 sensors, but the PCM has been tuned for headers. But the O2 sensors may be to blame? The O2 sensors are new, got new ones with the engine swap. And I dont have a check engine light code on for bad O2 sensors...

Injuneer

Shorty headers do not "throw off O2 sensors". Who told you that? Cera-metallic coated headers may contaminate the sensors with the initial burn-off. Slathering anti-seize on the threads, or handling the sensors carelessly can contaminate them. Dripping fluids on the outside of the sensors, running leaded fuel, etc can damage them.

What brand are the O2 sensors? Generally, anything other than a GM (Delco or Delphi) sensor will not provide good results.

MathalomuleM31

Im almost positive they are AC Delco. I read on a few posts a while back, that headers, because of the high flow output (My Catalytic converter is also gutted out) , can "Throw off" O2 sensors. I suppose shorty headers wouldnt throw em off.

Headers, o2 sensors, need a tune or not? - The Mustang Source - Ford Mustang Forums

But all in all honestly I believe my O2 sensors are fine. Theyre new, good brand, and i dont have a check engine light code for that problem. But if push comes to shove ill check them after the other things on the list. Ill post results as i get em, wont be able to get her in the shop till tuesday

Injuneer

Hmmmmm.....

Just proves you can't believe everything you read on the internet.... above is total BS.

Chose to believe whatever you want. We tried to help you.

MathalomuleM31

its not that i dont believe you O.o You asked where i heard it, i told you haha. I appreciate the help. I wanna go in fully ready and swinging at this problem is all. Im just trying to expand my knowledge so im prepared for this when i get it in to fix it.