My younger son got himself a 89 formula few months ago with a TPI ZZ4 motor in it which its not the original motor well bottom half is new but he is having issues with it bogging down when driving, he stated RPMs would jump from 500 to 2000? He also said he can turn car off and back on and it starts up we thought maybe fuel pump but since starts maybe not. what can it be? Any help is appreciated. Forgot to add this, he did have a code reader test done and nothing came up?
we did do fuel gauge test and got 35 psi when at idle under load at 2000rpm pressure bounces from 32 psi to 36 psi is this good pressure be at? I know this is a Pontiac but has Chevy motor though where would the fuel filter be at?
All vac lines look good. Spark plugs and wires good, gap is .040.
What should the OHMs be for the injectors we will check them too
Next thing we will do is check timing once get the gun from my brother.

Him and I are new to this TPI stuff well I have 4 door 57 Chevy Belair with 37K on it little easier work on .
I was told on another site I belong to for my Chevy we need do A Google search for Moates and would be a good start for the research for TPI stuff.

Sorry for all the question as I said new to the TPI stuff. But proud son got an some-what older car with a chevy motor in it and it does sound good LOL.

 

Pressure is low , should be 43.5+ with the vac line off ; dropping to 39psi @ idle with line connected
Moates is equipment for custom tuning ; not generally required for normal , stock (ish ) engines

 

Thanks for the info. Sons coming by tomorrow we will look more into the fuel press and see if we can change out the fuel filter. Also we will do the OHM checks too and check the timimg.

 

I don't think its your fuel pressure although it is a bit low, I would be looking at the AIC valve or maybe you need to adjust or replace your tps. these are both on your TB.

As for the moates site, it would be a good idea to look into, If you get the ALDL cable from them you can do data logging to see what your engine is actually doing, If you get the mind to do some tuning you can then get the equipment to start doing that, The ZZ4 engine you have ha a bigger cam than what the original engine had in it, So getting a chip made for your new engine or programing a new chip would have the engine performing better.
Do you know what size the original engine was?
The 305 and the 350 use different programs in there chips. Also use different fuel injectors and knock sensor.

 

You need to establish if you have the correct 350 parts installed if the car was originally a 305.The computer is the same but the "tune" on the removable chip inside it is different

Ist port of call would be to to pull the engine error codes and see if anything is showing
https://www.thirdgen.org/forums/tech...s-dumbies.html
What the codes mean
http://www.hotrodhandbooks.com.au/eB...Line-08-3.html

This cable
http://www.aldlcable.com/
and some free software lets you see what the engine is doing in real time

 

Hey all thanks for all the info I saved most of it to my laptop and will show the son. Im not sure what motor was in it before son and his mom went at looked at car and bought it so i wasn't there to get all the info on it. Ill ask him today when he comes by what motor was in it. Thanks again
Ok just talked to him it was a 350 original motor in car.

 

If you need any assistance tuning send me a pm, I did a live tune on a tpi zz4 a few months ago and was able to pickup 20hp and 40tq. With 30#hr injectors it was running lean at 13.5:1.

 

Hi all we check all injectors all .017 so we good there. We looking at the timing and marked the line on balancer we marked white and the mark is say a good % to the left of the mark on motor. Where should it be at?

 

6-8 advanced with the est disconnected. The heads like more timing like the corvette ARAP .bin.

 

Ok after tinkering around we got it timed right and seems to be running strong. Thanks for all the help. Now he wants more horse power but hmmm he'll be 21 soon and don't think so LOL maybe in few years LOL

 

Hi all, Sons car is still missing a beat at times it would run good then at times seems to hesitate and run good. We got a aldl cable in, tunerpro download to laptop and we will plug it in today to see whats going on. Hopefully we'll get some snap shots and show you all whats up. What else do we need for tunerpro to work?
Got a silly question where is the Cooling temp sensor located at? WE been reading up and this can cause issues too. We will replace it also today. Thanks.

 

Download the $6e adx if its only listed as a ads convert and save as a adx in TP.

 

Ok cool thanks Ill have son take look at all the download stuff hes going to school for computer science so maybe he will understand all of this better than me .

 

Fuel pressure should be in the 46-50 psi range if this still has stock injectors. 355 hp engines struggling to drink with 240 hp worth of fuel delivery.

 

After playing around with Tuner-Pro Sunday with son on his car we decided to pay for the Tuner-Pro RT we couldnt get the other program to connect? But got the RT one going and reading the car but we couldnt save anything or start the recorder we get a file error anyway to fix this because we want save it and maybe post it here and see what you all think whats going on with the missing at times.
We had 2 error codes , 32 and 42. We looked around for issues did find number 2 plug wire arcing to the exhaust manifold we adjusted wire away from it and no more arching should we change all wires they all seem to be newer? Also seems to be tight fit for all wires near mainolds and wondering if see below pic be good to put on wires? We keep reading up on the TPI stuff and seems few have issues like we are having with it missing a beat at times? More input be cool from you all?


Cool It Plug Wire Sleeves should we get these?

 

Its been a while since I played with the OBDI GM stuff regularly, but IIRC code 32 is an EGR error. No suprise this code will show up if the EGR is not shut off in the ECM. Only way around this would be external EGR from a Corvette with the ZZ4s lack of EGR passageways in the heads. Otherwise disable the EGR in the .bin and burn a new chip to run without it.

Code 42 is for the ESC circuit. IIRC this one can be set while adjusting the timing and stay in the system up to 50 starts if it is not cleared by removing the negative terminal. I would clear the codes and see if this one comes back. It may very well be nothing to worry about.

As for the plug wires and boots, if you have bad wires no amount of tuning is ever going to cover up a mechanical issue. A quality plug wire and good heat insulator is manditory in my experience.

 

Fast355 thanks for the reply. Ok we will check on the ERG issues.
The code 42 did go away after took off the neg side of batt we notice little crosion on it.
The Plug wires he has on car are MSDs not 100% sure if they good ones or not. But we will replace them too make sure. Also the sleeves in my last post are those good to put onto the plug wires as too me most plug wires do run close to the headers and such.

 

I'm sure those sleeves can't hurt, and in some modified applications they may really help, but with manifolds, you know a zillion other people routed the wires with no issues, so I don't know that they're really needed. Like Fast355 said, there's no replacement for good quality plugs and wires.