Lt1 will not start
02-09-2014, 02:46 PM
#1
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Lt1 will not start First of all, I'm new to the forums so hey everybody!
Now my 93 Z28 won't start, Im assuming and I'm pretty positive its the optispark. But i was wondering if anyone else had any ideas. It turns over, won't start, and a week before it stopped running it would stall. Sometimes i could start it back up and sometimes i would have to wait 3 minutes before it would start again. So at first i thought maybe the fuel filter was clogged so i replaced that, and it still wouldn't start. So now I'm stuck thinking its the distributor
Now my 93 Z28 won't start, Im assuming and I'm pretty positive its the optispark. But i was wondering if anyone else had any ideas. It turns over, won't start, and a week before it stopped running it would stall. Sometimes i could start it back up and sometimes i would have to wait 3 minutes before it would start again. So at first i thought maybe the fuel filter was clogged so i replaced that, and it still wouldn't start. So now I'm stuck thinking its the distributor
02-10-2014, 08:53 AM
#2
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First of all, I'm new to the forums so hey everybody!
Now my 93 Z28 won't start, Im assuming and I'm pretty positive its the optispark. But i was wondering if anyone else had any ideas. It turns over, won't start, and a week before it stopped running it would stall. Sometimes i could start it back up and sometimes i would have to wait 3 minutes before it would start again. So at first i thought maybe the fuel filter was clogged so i replaced that, and it still wouldn't start. So now I'm stuck thinking its the distributor
Now my 93 Z28 won't start, Im assuming and I'm pretty positive its the optispark. But i was wondering if anyone else had any ideas. It turns over, won't start, and a week before it stopped running it would stall. Sometimes i could start it back up and sometimes i would have to wait 3 minutes before it would start again. So at first i thought maybe the fuel filter was clogged so i replaced that, and it still wouldn't start. So now I'm stuck thinking its the distributor
02-10-2014, 09:12 AM
#3
First of all, I'm new to the forums so hey everybody!
Now my 93 Z28 won't start, Im assuming and I'm pretty positive its the optispark. But i was wondering if anyone else had any ideas. It turns over, won't start, and a week before it stopped running it would stall. Sometimes i could start it back up and sometimes i would have to wait 3 minutes before it would start again. So at first i thought maybe the fuel filter was clogged so i replaced that, and it still wouldn't start. So now I'm stuck thinking its the distributor
Now my 93 Z28 won't start, Im assuming and I'm pretty positive its the optispark. But i was wondering if anyone else had any ideas. It turns over, won't start, and a week before it stopped running it would stall. Sometimes i could start it back up and sometimes i would have to wait 3 minutes before it would start again. So at first i thought maybe the fuel filter was clogged so i replaced that, and it still wouldn't start. So now I'm stuck thinking its the distributor
Check the fuel pressure as mentioned, then diagnose the ignition: ICM, coil, then opti.
02-27-2014, 06:50 PM
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The ICM going bad will cause that sometimes too, they are known to cause random starting issues, random stalling, or just completely take a dump. I've been through 3 or 4 of those over the years Check the fuel pressure as mentioned, then diagnose the ignition: ICM, coil, then opti.
Check the fuel pressure as mentioned, then diagnose the ignition: ICM, coil, then opti.Last edited by 93camroZ28; 02-27-2014 at 07:04 PM.
02-27-2014, 07:27 PM
#5
Wow i actually never thought that it could be the ICM. I thought those normally go when its like really hot out? I was driving around in snow when it died and wouldn't start up again. But all the symptoms match up to the ICM. Sooooo, the opti may not be the problem, right? I had no spark. And its nothing to do with the fuel pressure, i figured that out.
02-28-2014, 11:03 PM
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They can go bad regardless of temperature, I believe auto parts stores can test them, they are much cheaper and easier to replace than an opti for sure. Then again it could possibly be the opti too....is random stalling and having to wait to restart it the only symptom? Scan it for codes and see if you get the 3 opti codes of death: http://www.gmhightechperformance.com...ing_modifying/
. It did it first when i was driving normally(25 mph) and once when i was doing a burnout lol. I was able to drive back to my house nor problem after those stalls. It also has no oil pressure. Im assuming its low on oil, I'm going to check tomorrow morning after it has cooled off Trending Topics
03-03-2014, 06:01 PM
#8
Well it ended up being the icm. I went out on a limb and bought one and replaced it. It started right up even though it hasn't ran in two months. Stalled out twice though . It did it first when i was driving normally(25 mph) and once when i was doing a burnout lol. I was able to drive back to my house nor problem after those stalls. It also has no oil pressure. Im assuming its low on oil, I'm going to check tomorrow morning after it has cooled off
. It did it first when i was driving normally(25 mph) and once when i was doing a burnout lol. I was able to drive back to my house nor problem after those stalls. It also has no oil pressure. Im assuming its low on oil, I'm going to check tomorrow morning after it has cooled off
03-09-2014, 08:24 PM
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I think i may of exaggerated how low the oil pressure is. Its actually has gone back up.
03-14-2014, 10:35 PM
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Update: Replaced coil tonight. Car started right up. I think it might be running better also. The old coil was beat to f*ck. All rusted and whatnot. With a new ICM and coil i think the stalling problems are done(I hope). I tried driving around my town(which is 1 square mile so i didn't go too far) as much as i could. Back when i replaced the ICM, i couldn't even make it a couple blocks. Tonight i drove around with no problem. It hesitated to start once after i had parked and went a store for about 10 minutes, thats all i really can think of.
The low oil pressure problem doesn't seem too bad anymore.
Sputtering seems to still be occurring.
Im going to see how it goes over the weekend.
The low oil pressure problem doesn't seem too bad anymore.
Sputtering seems to still be occurring.
Im going to see how it goes over the weekend.
03-15-2014, 10:50 AM
#12
For the Opti going bad, you will almost certainly be throwing a code. Is your MIL on? Someone asked before but you never indicated otherwise.
I have just recently had the experience of a bad fuel pressure regulator where it would cause a no start condition on my LT1. I would take a peek at your fuel pressure. See what you get when you prime, when you crank and when you are running. All three should be in and around 41-45 lbs if you are running a stock fuel setup.
How low are we talking about oil pressure? Is the engine warm when this happens? How many miles does it have?
I have just recently had the experience of a bad fuel pressure regulator where it would cause a no start condition on my LT1. I would take a peek at your fuel pressure. See what you get when you prime, when you crank and when you are running. All three should be in and around 41-45 lbs if you are running a stock fuel setup.
How low are we talking about oil pressure? Is the engine warm when this happens? How many miles does it have?
03-15-2014, 11:37 AM
#13
For the Opti going bad, you will almost certainly be throwing a code. Is your MIL on? Someone asked before but you never indicated otherwise.
I have just recently had the experience of a bad fuel pressure regulator where it would cause a no start condition on my LT1. I would take a peek at your fuel pressure. See what you get when you prime, when you crank and when you are running. All three should be in and around 41-45 lbs if you are running a stock fuel setup.
How low are we talking about oil pressure? Is the engine warm when this happens? How many miles does it have?
I have just recently had the experience of a bad fuel pressure regulator where it would cause a no start condition on my LT1. I would take a peek at your fuel pressure. See what you get when you prime, when you crank and when you are running. All three should be in and around 41-45 lbs if you are running a stock fuel setup.
How low are we talking about oil pressure? Is the engine warm when this happens? How many miles does it have?
04-03-2014, 01:53 PM
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So ive come to the conclusion its something to do with the fuel pressure. Ive done everything ignition wise possible besides opti. Its running great beside the fact it stalls. It always stalls at operating temperature. So ive been driving around with my heat on blast. Oddly enough that works, when i have the heat on the temp drops 15 20 degrees which actually helps. My heater core is broken or something cause the heat doesnt work anyway lol.
04-03-2014, 02:40 PM
#15
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So ive come to the conclusion its something to do with the fuel pressure. Ive done everything ignition wise possible besides opti. Its running great beside the fact it stalls. It always stalls at operating temperature. So ive been driving around with my heat on blast. Oddly enough that works, when i have the heat on the temp drops 15 20 degrees which actually helps. My heater core is broken or something cause the heat doesnt work anyway lol.
04-11-2014, 08:22 PM
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So i tried that temperature sensor thing. Didnt fix it. I checked the fuel pressure, it was good. What should i try next. Keep in mind that it sometimes stalls at operating temperature, stalls after its reached operating temp and its cooled down(so not operating temp) and sometimes it doesnt even start. Distributor? I also did the icm and ignition coil. Maybe the icm is failing? It wouldnt stall at operating temperature or at all for like a day with the new icm, then it started happening again. I havent dealt with a opti problem yet. The guy i bought it fron sad his girlfriend would run through puddles all the time he said he replaced it like 4 times.but i started experiencing problems just randomly. I was going down a dry road about 60 mph and it stalled and started right back up and the problems got worse.
04-11-2014, 11:16 PM
#19
I thought I recalled the coolant temp sensor on the water pump linking to the gauge and the coolant temp sensor on the drivers side of the block linking to the pcm. I may be wrong, but if im not, the temp would read correctly on the gauge but not on a scan tool or pcm. In this situation you would get a hard start, and will run like crap. Either way scan that computer before replacing random parts!
04-12-2014, 12:28 AM
#20
So i tried that temperature sensor thing. Didnt fix it. I checked the fuel pressure, it was good. What should i try next. Keep in mind that it sometimes stalls at operating temperature, stalls after its reached operating temp and its cooled down(so not operating temp) and sometimes it doesnt even start. Distributor? I also did the icm and ignition coil. Maybe the icm is failing? It wouldnt stall at operating temperature or at all for like a day with the new icm, then it started happening again. I havent dealt with a opti problem yet. The guy i bought it fron sad his girlfriend would run through puddles all the time he said he replaced it like 4 times.but i started experiencing problems just randomly. I was going down a dry road about 60 mph and it stalled and started right back up and the problems got worse.