I don't get it. It fires up straight away when its cold. Runs fine. But when I try to start it up when the engine is warm, it cranks and cranks and cranks and limps up to full rpm idle. Then it runs fine. I changed the plugs, rotor and cap, and fuel filter. I even put some methyl hydrate in my fuel. No change. I'm worried that it won't start up one of these times.

I have 185 KMS on it. Its a 2001 Blazer Vortec 4.3 V6. Any ideas?

 

Sounds like the ignition control module (ICM) is getting hot and malfunctioning. AutoZone can test it for you.

 

ok... i purchased a new ICM but it still doesn't start right. OK OK OK.... it wasn't a new ICM. it was used off ebay for $10. I just can't bring myself to pay $175 for a new one if that ain't the problem. So perhaps the used one I bought is bad also but hard to believe. There is no Autozone here in Canada and I can't find anyone who can test it. Does any one know how I can test this myself?

 

anyone?

 

Alright guys... I need help. The starting is getting worse. Burned out my starter because it takes several seconds longer then it should to start up. Got a new starter but I don't know how long its going to last. Most of the time it fires up with a small crank. Doesn't matter how long I drive for, I park it for 20 minutes and it cranks and cranks and cranks cranks before limps to a start. The engine light came on for a day or two before it turned its self off. I purchased a pretty good code reader and it was a P0300.

I've changed all plugs, rotor and cap, fuel filter, and ICM. Do I just keep throwing parts at it? Should I do the cam position sensor next?

 

Have you tested the fuel pressure?

Have you had any luck finding a place to test the ICM & coil?

 

I haven't tested the Fuel Pressure. I'm guessing I will need to purchase a fuel pressure guage? Is there a specific one I need to buy? I haven't found a place to test the ICM. The Hynes manual I have shows how to test the coil. I can do that. But my questions are these...

If the Fuel Pressure is low, would that have caused the engine light and the P0300 cylinder misfire code? Or a bad ICM or coil for that matter?

I notice that low idle sounds and feels a little rough. and if I step on the gas just a wee little bit, there are some hesitations and the RPM seems to fluctuate. Step on the gas just a little more and it seems to run fine. Just seems on warm start up some cylinders limp up to run. and very very little throttle runs kind of rough.

 

Truck is in the shop. The guy says it is prob the fuel regulator and injectors. He will test and get back to me. He scared the $$^% out of me when he said he just did this on his cousin's van. Said the injectors were $160 ea!!!! and charged his cousin $300 labour.

Is it hard to change this myself? Is there special tools needed? I see on ebay there are refurbished CPI Spider Injectors for about $90. I've also seen new ones for about $250 +. I've rebuilt may 2 stroke dirtbike and I'm very mech savy. I'm big on doing this myself and saving a ton of money. Any tips anyone can offer?

 

Hey. I've read a lot of posts related to this subject but they never seems to have an end result. I figured I'ed post for clouser.

The shop confirmed the fuel regulator looks to be leaking. Highly suggested to replace the old single port spider injector with the new redisign multi-port injector which includes the regulator. He said its a big job and that he would charge me $1700. He also said I prob need a new cat as well. So I took my truck home. I purchased the Spider for $350 from Lordco Auto parts and did the job myself. It wasn't as hard as I thought. Clearly the regulator was leaking. no more starting problems or hesitations. However, the P0300 code is back. Perhaps the cat is clogged as a result of the it running rich from the leaking regulator. I figure I'd drive it like I stole it for a good while and see if I can burn it out. hahaha.

Anyways... thanks. I'll let you know if I end up buying a new cat.

 

Glad you got it done for a lot cheaper plus now have the satisfaction & confidence gained from doing it yourself.

Don't go back to that shop! They didn't know what they were talking about when they explained the injection systems to you and tried to rape your wallet with that quote for doing the job.