MAF or IAC ?

[AirBrontosaurus]

You can buy dataloggers, but they are sort of expensive. You can get one from SCT for about $150, but I've never used it so I cannot comment on its effectiveness. I do my own tuning, so I have an interface box and program that allows me to upload tunes, as well as connect my laptop to my car and read what the ECU is doing. My setup costs about $350, but most of that is for the tuning side. You can buy just the datalogging, but I think it's around $250. Honestly, it's probably not worth it if you're not going to tune by yourself. However, if you have a friend who has one, or know someone at a tuning shop, then you can use their hardware for logging. Unlike tuners, loggers aren't tied to one car and can be used as often as you want.

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[dg98gt]

Man, 75 is not good. Put some oil in that spark plug hole and try checking again. See if the number gets higher than 75. If it goes much higher....140-175 like the others, your rings could be toast. If it doesn't.........it could be a head gasket, valve seals, or worse, a hole in the piston.

Good luck,
Derrick

[N2Gaming]

I did a wet test on cyl 8 and it jumped to 300 and I retested a few more times and it averaged 270-280 while wet w/oil.

So I put the cleaned plugs back in and still the same thing.

Is it possible to pull the fuel rail w/the injectors to see how they are spraying out side the heads?

Also what is the best way to check for ignition spark?

Thanks guys.

[dg98gt]

Wow, that's a big jump.........something doesn't sound right. How much oil did you add?


You can buy a spark tester at autozone for cheap.

Later,
Derrick

[cjhstang]

Originally Posted by N2Gaming

Is it possible to pull the fuel rail w/the injectors to see how they are spraying out side the heads?

Don't think so. Injectors are sandwhiched between the fuel rail and the injector hole in the intake. Have to take the injectors somewhere to be tested. You can try switching your 'suspected' bad injector with one you 'believe' is good...

Originally Posted by N2Gaming

Also what is the best way to check for ignition spark?

I pull the spark plug out and plug the wire back onto it and set it on a grounded part of the car and turn the key. You may not see spark but if you hear crackling then your good.

[dg98gt]

If you can keep the car running............I usually troubleshoot fuel injectors like this.

1) start the car and pay attention to how it is running
2) Pull a plug on each injector (one at a time) and make sure the engine "sounds" different.
3) If you pull one (or more), and the engine sounds the same as before, then it narrows it down to that cylinder.
4) It could still be spark at that point, but you should narrow it down to 1 cylinder hopefully by that point.

Derrick

[dg98gt]

If you can keep the car running............I usually troubleshoot fuel injectors like this.

1) start the car and pay attention to how it is running
2) Pull a plug on each injector (one at a time) and make sure the engine "sounds" different.
3) If you pull one (or more), and the engine sounds the same as before, then it narrows it down to that cylinder.
4) It could still be spark at that point, but you should narrow it down to 1 cylinder hopefully by that point.

Derrick

[N2Gaming]

Well I picked up a spark tester for 3 bucks at Kragen/Orylies w/some new Motorcraft SP-432 spark plugs.

The car has spark on all 8 cylinders. So I went to get the car running again w/the old plugs to blow the oil out before installing the new plugs and used a bit of starting fluid but this time the car does not want to stay running. IDK I think my car is upset now and telling me

[TheAndyManCan]

wow this is like the exact same problem im having...try unplugging the MAF and then starting the car while cold...if it starts up and idles fine i think weve got the exact same problem. mine will start up and idle perfect with the maf unplugged but with it plugged in nothing but continually feathering the throttle will keep it from stalling. then when it gets to normal operating temp i can get it to start and idle kind of ok with the maf plugged in but then when its holding its idle sometimes it will just cut off like i turned the key off or something. i mean the electronics stay on and everything but the engine just shuts off real fast.

so then while it was holding its idle i decided to pull it out of the garage and try to drive it. so i put it in gear and give it some gas while easing off the clutch it stalls as soon as i let all the way off the clutch. start it back up and ive got to rev it up ease off the clutch rev it up again and repeat before it dies and do this over and over basically inching forward limping back into the garage. i thought i just had an idle problem but no i cant even drive without it stalling its like it can even handle the load of driving. my car is a 01 gt with a p1sc procharger, 42lb injectors, lightning 90mm maf, exhaust, throttle body+intake plenium, ngk tr6 plugs at .035, and i just recently got a sct x3 tuner with a simple base tune to get it to the dyno but the problem was their before i loaded up the tune and still there after. HELP ME!!

[dg98gt]

Typically, if you unplug the MAF, and the car runs fine. You either have a bad MAF.........or a vacuum leak somewhere that is letting unmetered air in.

I would try that and my little fuel injector test.

Good luck,
Derrick