Hi everybody! I just got finished swapping in a edelbrock e-tec 355 into my new 1991 GTA. I used the SDPC Vortec Intake base with stock runners/plenum for now and 25# slp injectors (ls1?). But, that is not the problem. I got everything hooked up and installed (looks great btw) and I've been having a problem with the engine dying at idle (and when moving it cuts out).. I have all of the burning equipment and Moates' 29F040 chip adapter. I made a new program using a AUJP bin and changed a few things like disabling the EGR, fixing the fuel injector constant and changed the fan enable temps. When I have the laptop connected using Moates scanning software, the data stream will cut in and out (sometimes I have to restart the program). When it cuts out while moving the speedo drops to zero and the SES light comes on.. I have tried using the stock memcal and stock chip and it doesn't run very well so I think my eprom is good (runs/idles well when its not cutting out)...

One other thing I noticed is this: When I simply turn the key to on (without starting the engine), the SES light will blink intermittently and the no. 1 cooling fan will occasionally activate then shut off after a few seconds... This is without any scanning hardware hooked up... Curious...

I'm just getting started with this eprom burning stuff, but I don't think thats my problem.. Any help that you guys could offer would be great, I've been reading this board for a while now, but can't figure this one out..

Thanks,
Kevin

 

Sounds like you have an ECM or prom seating issue. I'd check that first.

May be going in and out of limp mode.

I woulda left the constant alone under you at least got the engine running.. The lower constant mighta helped, cuz with no doubt your ve tables are gonna be waaaaaaaaay off. Now with the higher constant, its trying to supply way less fuel.



-- Joe

 

When I do have the scanner running my blms go down to 108 after it goes into closed loop... This would mean the computers trying to take away fuel, right?? With the VE tables incorrect, would this behavior be incorrect as well or can I trust the blm's??

 

Yes.
Incorrect being a relative term.

Trust them to do what?.
If things are mechanically correct, then you can tune to get the BLs to be about 128. +-4 is generally accepted as close enough.

 

I don't know if I can help you, but I have a '91 Z28 and just had Scoggin-Dickey build me a motor w/their Vortec intake and you have to use Vortec style heads, I chose the Aluminum FastBurn heads. I used TPIS stuff on the rest. There is a left and a right to the runners that I have heard with make your motor run bad. I would like to know if you are doing reprogramming or just gathering data and what you are using to do so.

Good Luck..........

 

definitely sounds like an intermittent with your eprom or something related(adapter, etc). Double and triple check everything, you may also want to remove all the chips/adapters and check for a bent pin. It is possible that a bad ground might do that was well, check for the straps that should be attached at the rear of the passenger side cylinder head. Hope that helps.

 

Just remebered you said you used the stock runners.
I used TPIS runners and they are bigger than stock must match up perfectly with the SDPC Voretec TPI base.

 

Well, as it turns out, the ECM was to blame.. I checked and double checked all my connections and decided to go and try a new ecm.. That solved it... Now the car won't cut out and die (still have tuning to do, but that I know).. Now I get consistent and uninterrupted data from the ecm..

Davey, I'm using a laptop with Moates software for data aquisition and monitoring and I've got a pocket programmer ii for the chip burning and I'm using Moates 29F040 adapter for the eprom so I can use up to 16 different programs eventually...

This process was frustrating just because I was excited to get started making chips for it. Here I thought I was screwing something up there, but it turned out it was the ecm puking on me... Thanks for all the help, time to see how the tuning process goes!!!

Kevin