Cant seem to understand what's wrong with my setup. It's a 1993. Took it for a drive today after the motor swap and noticed that when idling the RPMs jump from 1k to 1400k, when coming to a stop it bogs and wants to die, alot of the time when I did come to a stop it bogged, and when I would try to go past part throttle or wot it would bog.
Feels like it's getting to much fuel. My mechanic told me that with the stock injectors it runs like night and day (much better). My question is what's going wrong with my 37# Racetronix injectors? They worked fine with the exact same motor when it was in my 94 Camaro. Now in the 93 I'm having issues. I looked over my tune and the only thing that seems a little off is my injector flow rate is set at 40.3. I dont feel that's the reason though. If someone can look over my tune that would be great but as far as I can see it looks fine and Alvin says it's fine.
What am I missing here? I didnt notice any vacuum leaks or anything unusual motor wise so what else do I need to look at? We took the motor from a 94. Is there anything electronic on the motor for 94 that doesnt work with the 93 setup that could cause these issues?

 

What did you do about your previous post, where you indicated you don't have the IAT sensor or the O2 sensors hooked up?

 

Got everything hooked up. I was sure it would solve the problem but it didnt. Now I'm stumped and fustrated beyond belief.

 

Have you tried forcing it into open loop to see if the problem subsides?

 

No we havent. It seems like a open loop issue thus far. The thing that keeps throwing me off is the fact that now it runs fine with stock injectors, idles really high (1100rpm's set at 900 through the tune) but drives ok at part throttle. I think I'm going to try to send the complete pcm and chip to PCM for less to see if it's a pcm problem. That means the car could be down another 3 weeks due to shipping etc. I want that to be last case scenario though. I'm really running out of ideas. I looked over the tune 3 times and cant find anything out of the ordinary. Fuel psi is fine, everything is connected and no apparent vaccum leaks. Engine idled fine in the last car. The only differnce from car to car is the chip and the fuel rail. What else should check?

 

Obvious question here, but how old and in what shape is the opti? They can be very tempramental, and it is possible it might have gone on you in the swap.

 

Brand new Dynaspark installed according to directions by a pro. For the first time ever I think I can actually rule the opti out as not being the cause .

 

So does it get better, worse or stay the same when it goes into closed loop? My suspision(spelling) would be the O2's are not reporting correctly.

Have you looked to see what the O2's are doing versus what the ST and LT fuel trims are doing? Particularly with both sets of injectors installed?

Since stock injectors flow less than 37#(93's are 22# and 94 and up are 24#), perhaps it is trying to richen up the mixture too much and the stockers obviously can't put out near as much as the petronixs can. I would be concerned about crankcase dilution also.

Viewing the O2 signals at the same time watching the ST fuel trims could help. That's why I mentioned forcing it into open loop with the pertronix units installed since it will (or should revert to a fixed enrichment table) depending on what your tuner did with the program.

Forcing it to open loop could help in the diagnosis. Also are you still using batch fired injection or sequential?

 

Closed loop the idle is still iradic. Adjusting the idle screw is getting me no where. Driving below 2k-2.5 it drives like crap. Above 3k it's ok. Below 3k it bogs and gurgles and is really rich. Kinda chugs along. I'm going to start datalogging it in the morning. I'm still batchfire. Cant go seq because of the BCM.