jrock692

iTrader: (4)

Okay guys. My car wouldn't start. It will turn over good, but wont hit, well not often at first. The more you crank on it the more it will start to hit. After several minutes sometimes it will start sometimes not.

I checked fuel it was good at 43ish pounds at the shrader valve. (new pump) I pulled the number 3 plug and it is black. Put it back in the wire and against the header, and while starting got an occasional light spark. I changed the plug to a new one I had laying around and it arched good. I replaced it and it hit on that cylender good.

This problem has happened several times. Since it has started doing this I have replaced the wires(to 8.5mm summits)and plugs (tr55 gapped to .45).

My question is with new plugs and wires, what could be causing my plugs to foul?

Thanks for your help

djjab57

iTrader: (17)

check the coil and ICM

jrock692

iTrader: (4)

Okay i found another new plug changed it and got it to start after missing loping and all kinds of other crap all the cylenders started hitting and i got it into my shop to pull the coil.

The only test procedure I could find is on shoebox. It says to check ohms from all four connections to the main terminal. I get nothing. The needle will not even budge. Bad coil??

And I can not find a procedure to check the ICM. Can someone chime in on this for me?

Thanks guys.

bigj2717

iTrader: (15)

The way I've always checked the coil is pull the wire from the opti and hold it close to the head and get somebody to turn the key and check if its sparking

jrock692

iTrader: (4)

I am getting spark to my plugs and that would be the same thing right? Just think it might be weak spark. Back to the original post my plugs keep fouling.

bigj2717

iTrader: (15)

Will if the plugs are fouling and you're getting spark it could be an air/fuel issue. What injectors are you running? I see you're running a 58mm maf why so big with just bolt ons?

jrock692

iTrader: (4)

Stock injectors. And I thought they may have been leaking causing it to flood, but since have bought new ones and replaced the original ones. And thats a 58mm throttle body, not a maf sensor. Do they make that??? Anyway, I am running a 58mm tb because of future upgrade path. Why replace it with a 52 if later I will need a 58 anyway. Also It was doing this before the tb upgrade.

bigj2717

iTrader: (15)

Haha my bad typo. Well if you're running stock size injectors it could be the tune too. How old are the plugs and are you just replacing one at a time?

jrock692

iTrader: (4)

Yea I just replaced 2 today as that is all I had. The plugs that are/have been in there are not very old at all. maybe have a couple hundred miles on em if that.

bigj2717

iTrader: (15)

Well too me it sounds like stuck injectors or the tune. And since you said the injectors are new I would lean to the tune or o2s could be causing it to run rick and foul the plugs

jrock692

iTrader: (4)

I wouldn't think the injectors are sticking as I can pressurize the fuel system and come back the next day and it is still holding the same pressure as the day before.

Back to the original post. Can the coil get weak, but still fire?

bowtienut

iTrader: (1)

Yes, it can.
You have an ignition problem. Forget about the fuel system.
Coil, Opti, or ICM.

moehorsepower

iTrader: (3)

Even though you are getting spark at the plug, On a new plug, look at the color of the spark, It should be a blueish, if it is like and orange/yellowish color then its a weak spark....

jrock692

iTrader: (4)

Thats what I was thinking. Yea fuel should be good as pressure is good. And leaking injectors should be ruled out as it will hold pressure with the key off for days. And its a new racetronics fuel pump.

jrock692

iTrader: (4)

Yea it was a yellowish spark, not the normal whitish blue color you would normally see.

So if you guys read through the thread, is it normal to get that type of reading from a ohm meter while checking resistance on the coil? Seems to me the resistance is waaaaay to high.

And I can't find anywhere how to check the ICM.

x Wild Bill x

Why don't you just run down to Autozone or wherever, buy a new coil, bring it home and install it. If it fixes your problem, great all set, if not, put it back in the box and return it. Just don't put any dielectric grease on it for the test and they won't know you used it and can easily return it... Or find someone in your area that has an LT1 and borrow their coil...

Just my .02

Bill

jrock692

iTrader: (4)

I didn't realize a coil was so cheap. Its not payday and I could afford it! lol Anyway bought one from Autozone and just for the heck of it I put my ohm meter on it and it read just like shoebox said it should, so I guess mine was going bad.

djjab57

iTrader: (17)

Yea like i said $13-$14 at AZ, So is it running right now ?

its allgood

iTrader: (1)

i work at Advance Auto and they will take anything back. not suppose to! but they will take it back just like autozone. I just dont want to buy something that someone else tried....... lol

jrock692

iTrader: (4)

Yes it is running, however still hesitates to start when cold. I need to replace all the plugs as I know they were fouled before the coil install. I havent checked to see if the spark is hotter or not, I will do that tomorrow and post up the results.

The coil I got at autozone was 21.99 plus tax.

Wish forged internals were that cheap. lol