i've been having a problem lately, where my car either runs or doesnt. if i leave it sit for a few hours, it'll turn right over, no problems, and run just normal. if i drive it, get it to normal operating temp, turn it off for a couple minutes, then try to start it again, it gets no spark. the rotor looks fine, turns and all, but theres no spark.

what can go from working to not working completely? ignition module? anything i can test out with my multimeter or clampmeter?

 

Ignition module or pickup coil, maybe.

 

Ill vote for the module too!

But coil is another option too.


Either one will give you problems after they have run for a bit and warm up.

 

but by the same token, if i say, pull the coil and module, take them into autozone, (does it show in a gm service manual what leads to test and what voltages or resistance to look for?) and have them tested, wont they test just fine since they aren't warm?

also its only on start, shouldnt it run rough or die when im driving it around and its warm?

 

Well yes, some of the time a module does still test good on the bench when it is indeed fried.

 

pretty much all i can do is buy a new module and hope for the best then? could someone tell me how to test it myself so i can pull it and check it when my car wont start?

 

im having the same problem, and a hell of a time tryin to fix it. i dont think its spark thats causin the problem, i think its more like the injectors/ fuel system. when the engines hot, heat rise causes deposits to form on the end of already dirty injectors, so when little fuel, like on idle, is pushed through, it tends to sputter and misfire and build up. but when more fuel is pushed through it evens out. thats why theres no hesitation on higher rpms.

what ive found is that after driving, idle seems decent, but then misfires exponentially more and more. this has me leaning towards the fuel issue. if your car does this too, welcome to my world. i've also noticed that the fuel pump is working extra hard (i removed the interior and sound deadening, so i hear everything) so theres something amiss.. i also noticed that my fuel guage doesnt work, but thats somethin else.

im hoping the solution to this problem is as simple as replacing a clogged fuel filter, which is what i'll do tomorrow hopefully and i'll report what i get. i'll also run injector cleaner through the system.

-ian

 

doesnt sound like the same problem im having, the last couple times it wouldnt start, i checked for spark and it had none. actually now that i think about it, i tested the coil to dist wire too and it had no spark. should i just go ahead and get a coil?

 

If you want, but it's not guaranteed to fix anything.

 

I have the same problem when engine is warmed up it runs fine and no problem but if i shut it of its unable to start until i give it a minute or so then it starts just fine again,i was also leaning towards a faulty ignition type problem and as i have a chipped car its not a VATS problem.
I think i will order a MSD kit module/coil/8.5mm wires they had a drive on these 6AL modules on Summit just now so maybe could be a good deal also.

Rgds Mats

 

im using an msd 6al system, msd coil, pro billet distributor, 8.5mm wires, all msd system. if you find out what your problem is, please send me a private message.

 

i dont want to just start throwing parts at it, but noones been able to tell me how i can narrow the problem down anymore.

 

i just checked the codes, and it gave 34, 42, and 44. the 44 i think is from me playing with my timing all the time, i can never get the distributor to stay put. the 34 is probably from me undoing the maf sensor troubleshooting the car. the 42, says the est circuit is open or grounded or direct ignition system fault, or fuel cutoff relay circuit.

anymore thoughts?

 

Seeing as how you have a 6al box and ignition system. first things first have you tried bypassing the box so you just run off the coil. As the box gets hot and could be a problem as most do. However the est is looking like thats your problem based on the code. The only way to test it is to do a restistance test which isnt a very good test.

 

The first thing to do would be to removed the distributor, removed the ignition module, and have it tested at a parts store with a tester. I used to work at NAPA auto parts, and came across this a lot. It definitely sounds like the ignition module to me. If you let it cool down, and it starts, I would say ignition module. When you take it in to have it tested, tell them you want them to test it multiple times, until it gets hot. It will get hot to the touch when testing it. Some will pass the test cold, and fail when hot. That's why we always tested multiple times to get it hot. Let us know what you find out.

 

Seen a coil, pick up coil and ignition module all do this. Probably why I have about a dozen coils a few distributors and a couple modules kicking around.

You can search for Vader and pickup coil, he has, IIRC, a really clear write up of how to test it. The ignition module and coil bring in and have 'em try, but that's no guarantee.

Clear the codes before anything else, get the problem to recur and then verify that you are gatting no spark when hot.