ssduane

iTrader: (3)

So I have the engine/setup in my sig with the addition of, March underdrive pulley, MSD wires, Bosch platinum plugs, home port and descreened MAF, IAT is installed in air inlet. Stock size TB ( I did drill the air hole up to 9/64). Homemade longtube headers(one O2 per side), 2 1/2 exhaust w/X-over/mufflers. Did a mail order tune with the all the given info, except was tuned for stock MAF.

Heres my situation. The car starts fine, idle jumps a little, 900 RPMs. Put it in gear and it idles 800 rpms. Go to excellerate (in gear) and it stumbles a bit and takes off. Give it gas and let off and it dies, gets worse the warmer it gets. I get no engine codes and she seems to run rich. I pulled all plugs and they were black, cleaned them up and reinstalled. Seems to start better once I cleaned the plugs and drilled the TB a bit.

Do I really need to take it to the dyno shop and have it dyno tuned?

I'm getting ready to go overseas for 2 years and just want it easy to start and run so the wife can move the car in and out of the garage if need be, but don't wanna drop 5oo bucks right now to dyno tune if I don't need too.

BLK02WS6

iTrader: (2)

You should see if you can get someone to do a baseline tune a little cheaper for you till you get back. Needs to be leaned out in the idle and low rpms so it won't foul the plugs on her... You should be able to find someone around your area who could put 30 minutes into it for a reasonable price...

ssduane

iTrader: (3)

I was affraid of that. If been reading my *** off on tuning, how-to, what this does, what that does. I might just pick up a tuner kit and give it a shot myself.

Thanks.

Rob@EFIAlchemy

iTrader: (9)

ok first off why did you drill the throttle body, you have an adjustment screw on the side of the TB and your fouling plugs becuase you probly have an exhaust leaks. O2s are highly sensitive to air leaks within 12 inchs of the sensor. also porting the maf isnt the greatest of things either it can only read so much air now that you've descreened it its scale of air flow has been changed, this can also mess with your fueling. i would reccomend getting a tune, but before doing so check for any leaks in the system exhaust or vacuum because they will impact your tune.

BLK02WS6

iTrader: (2)

I missed the part about it getting worse when it warms up - that is probably due to your homemade headers leaking... you may want to have the tune locked in open loop until you can leak check the headers. Whoever did your mail order tune should be able to lock it in open loop so your wife can move it around without killing the plugs... Then when you get time, you need to see if those headers are leaking - if they are, you have to fix all of the leaks or have it tuned in open loop and leave it that way (kinda defeats the purpose of closed loop feedback capability though)...

ssduane

iTrader: (3)

Well, like I said, I've been doing a lot of reading, some are against it and some are not. Noted your opinion also.

No exhaust leaks, exhaust system is tight, same with intake, no leaks.

Looks like I'm leaning towards a tune. Thing is I had the PCM mail tuned, just figured it would run a little better than it is with that done.

Frost

iTrader: (45)

What he was getting at, is why did you do it? Because you read it or because you actually logged data that indicated that you need more airflow? If it wasn't for the latter reason (and you still could open the screw to lower IAC counts) then it was a mistake unfortunately.

edcmat-l1

iTrader: (10)

The best most accurate mail order tune will still run like *** if the car has mechanical issues. That's the variable that cannot be accounted for when doing mail order tunes.

Even on site tuning, if the car has issues, they'll need to be ironed out before it can be properly tuned. Anything else is just tuning "around" the problems.

PS, one of the first things you could do, is throw a stock unmodified maf in it.

ssduane

iTrader: (3)

I understand what he was getting at. No, I didn't log the data, don't have a scanner, so can't. If I had the cash laying around I would order the EFI or HP tuner and spend the time doing it. I have more time then money since I have been just trying to get the car together enough to move under power.

I figured I would try and drill the hole a hair more, I didn't go a whole lot, just some to see what it would do.

I think I'm good for now, but have just been trying to get more and more, instead of realizing that I just need to take it and get it done right.

I'm heading out to the garage and see what it acts like now, didn't spend to much time last night after drilling anbd cleaning plugs.

Thanks all for the input and not giving me the

ssduane

iTrader: (3)

Just got done playing with her some more. pulled the IAC out and it had a nice counting of crap on it. Cleaned it up and put it back in. Let the car run through a idle relearn.

Seems to run 100 percent better and a little leaner. Still a little rich though, but that will probably go away with a decent tune. She comes back to idle in gear after accelerating, so thats good. Not sure if it was attributed to cleaning the IAC, opening the hole a bit (not the correct way) or doing the idle relearn. Either way I'm happier.

Frost

iTrader: (45)

glad to hear it! I wasn't trying to give ya crap

ssduane

iTrader: (3)

I'm sure you weren't. I'm still a newbie when it comes to these. This is my first EFI mod, I'm used to carb'd Gen 1 motors.

Thanks to all.

Rob@EFIAlchemy

iTrader: (9)

glad to here its running better, the car may not be running as rich as you think, do you have cats?