usetaboost

iTrader: (1)

Does anyone have a list of scan numbers at idle for the lg4 ecm? Searched all over and can't find them. Figured there would be a sticky posted for this type of stuff but I guess not

usetaboost

iTrader: (1)

Nobody has anything on this?

naf

iTrader: (7)

I apologize for not being hep and understanding what you're asking for. Perhaps if rephrased I could maybe give some help?

makaveli09

do you mean a list of trouble codes the ecu stores ?
if so get a hayes manual they are cheap and are all listed in there

Tuned Performance

iTrader: (92)

or maybe the op means pw or the mc solenoid?

http://www.extreme-check-engine-ligh...%20Decoder.htm

usetaboost

iTrader: (1)

ok, let me rephrase this. First, I would like to know if winaldl can be used. 2nd, I would like to know what items need to be checked on the carb and how to check them. I'm new to the feedback carbs and carbs in general. All I've had is FI like my old tpi iroc and the GN I have now. I can tune FI, I just need a tutorial on how to tune the feedback carb and check things out to make sure everything is ok.

Some other things I need cleared up also. I know that the ab terminals need to be grounded to check timing, but what is best for the lg4? Is the 85 lg4 high or low compression? THere's mixed answers on the internet. I also read that the stock cam gear is retarded from teh factory. THis car has 132k on it, should I do the timing chain this fall when I replace some gaskets? My neighbor has a edelbrock performer intake I was gonna buy for 30 bucks and slap that on since I'm sure the intake gaskets are leaking a bit also.

Damon

Let me take a stab at a few of these....

85 was the first year the LG4 got the same (high) compression ratio as the L69 Ho (9.5:1). Also got a knock sensor like the L69 HO at the same time.

Stock timing is 0* with the timing plug disconnected. Not sure if you can ground the 2 ALDL terminals or not, but you can definitely unplug the flat 4-wire ECM connector that talks to the distributor. It's on a pigtail sticking out the back of the distributor above the transmission bellhousing.

I've found that a stock LG4 will take a setting 4-6* advanced over stock specs without much difficulty or downside. Some can take even more. And the timing "curve" for the LG4 isn't as aggressive as an L69 (different timing map in the chip).

The ECM on a feedback carb setup doesn't really have a fuel map per se. It's mostly either in closed loop (shooting for 14.7:1) or open loop- a fixed MC solenoid cycle map. Remember that the carb, by it's nature is doing 80% of the fuel metering automatically with the ECM just kinda "trimming" it under closed loop conditions.

Not sure if the factory used a "retarded" timing chain or not, but the cam in the LG4 is so small I'm not sure you'd notice much difference. Search for the term "penut cam" and you'll get plenty of info about it. With the miles on it, I'd change the timing chain if you happen to be in there anyway.

usetaboost

iTrader: (1)

Thanks for the info. I drove the car for about an hour last night and tried to really pay attention when it acts up. Like said before it stumbles off light throttle but I also noticed it does it when I let off the gas going down the highway. I also noticed that the TC switch engages as soon as it shifts into 3rd.