LT1 stumbling and missing now wont start
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
to begin with I did the cap and rotor. THere was a shitpyle of oil all over the cap. It was still running then. So When this started I bought a cheapo from ebay. But honestly it looks just like the one I took off.
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
Also the 94 motor in the car has the splined opti and really can only go in one way. It was definitly the whole way seated into the engine. I also saw on a couple other posts some people saying same thing about smoke in the intake and valve area and people were saying that will happen from extended cranking, Is there a way to see if my valves are opening when they should, or when I am getting spark when It should?
Launching!
Joined: Nov 2012
Posts: 253
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From: Midwest City, Ok
Re-reading the thread I realized about the 94 engine. If you didn't change the base of the Optispark then the relationship to the cam didn't change by the cap and rotor alone. So mark that one off.
I think the throttle body needs to be removed from the intake and a peek needs to be made inside the manifold. Also, clean the throttle body while you are at it.
I think the throttle body needs to be removed from the intake and a peek needs to be made inside the manifold. Also, clean the throttle body while you are at it.
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
what am I looking for? Now that you say that I did pull the cap off and look but i didn't take the rotor off and make sure that it was in the right spot but I spun it a few times to make sure that it spun freely. Maybe when they reassembled it after rebuilding it it wasn't put on correctly.(just guessing since it was only $100) the company who I got it from was KMJ Performance. Dont know if anyone has had any luck from these guys or problems
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
i guess since everything else has been tried ill do a compression test tom. when I did it last time it was when the injectors were screwed and all I did was pop the plug out and put the gauge in. and on no.1 and 3 I was getting around i think it was 75-90 or around in that range. But I think the injectors were messing that up. (i didnt pull all the plugs while i did the tests on 1 and 3. also the tester i rented from autozone was a real bitch getting in so after bi did those 2cyl that was when i pulled up the injectors and saw that mess)
Last edited by ugod02010; May 13, 2013 at 08:39 PM.
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
Justfor ***** and giggles I hooked up an old timing light up. I noticed I get two quick pulses a pause two quick pauses from the coil heading to the opti. But on the No1 cyl the engine will crank about 4-6 full spins of the harmonic balancer b4 I get a spark there. I hooked up on no3 and it sparks way way faster prob every revolution or two. My battery was pretty dead from all the cranking over the last 3 wks. so I could't go much farther than that. I will try a ffew more cyl. and see what is going on tom. morning. Sound like maybe the new opti I bought is junk?
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Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
No I haven't done the icm. I took it to all 3 auto stores around and none could check it. I tried the 12 volt and two5volt wire test and I think it was right. I just got home so in a bit here I am gonna go down throw the timing light on it and see what happens after I try a few wires. Should the coil wire spark 2 times quickly pause spark 2 quickly pause?
Launching!
Joined: Apr 2012
Posts: 233
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From: Crown point, IN
It sounds like your getting a pretty inconsistent spark.. And you've replaced most everything else. I would try and get my hands on an icm that you know works and throw it on there.. Worth a try
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
Well the answer was on the first or second page!? Hopefully anyways. I popped out the drain plug to get the old broken down oil out(from all the flooding) There was almost 4 GALLONS of fluid in the crankcase!!!!!!!!!!!!!!No wonder the s.o.b. wouldn't do anything. I filled 2 antifreeze jugs and 2 gallon tea jugs plus what came blowing out the other day and what i lost spraying ether in without the valve covers on when It started. I still haven't taken it for a spin still gotta fix a brake line that broke when I dropped the tank. and the exhaust needs hooked back up. Plus Alternator needs hooked up since I had the pass side valve cover off. I guess all the funny spark was from the battery being so low. Man I was gonna drain that oil out right after I put the injectors. Thanks again for all the help guys I'll keep you all posted what happens tommorrow when I actually take it for a drive. As long as things go smoothly.(Which they definetly have not so far). But now it will start under its own power turn the key and it fires right up. But i only let it idle for about 4-5 sec at a time about 3x since I don't have any oil in it.
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
Again I wanna thank you guys you have been a lot of help with troubleshooting this thing. (Much better than lookin in a book that was written at a desk without actually trying any of the stuff in it) I'll Post tommorrow and let you guys know whats up once I road test it. As long as it still starts
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
Seems to be! Thanks for the help guys. I am keeping my fingers crossed I got some new oil and filter and filled that up. Prob gonna get the alternator and stuff on over the weekend and actually road test it but it sounds healthy. Just loud as all hell with a straight pipe. I new there was gonna be a bit of fuel in the oil but I had no idea it had an additional 3 1/2 gallons of fuel in the crankcase. Musta been flooding even worse than I thought. Thanks again for helping out ill let u know how things go this weekend.!
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
okay finally got everything together. hoping to take a drive tonite and soon as i back out of the driveway and start up the hill instantly can tell no power. so i went around the block and i got terrible smoke out the tailpipe. Doesn't really smell rich like it was b4 just white smoke to the hills. and its really only when i give it some gas. also have a pretty bad backfire/miss again. Is it possible there is just still a pyle of crap in the cylinders from being so flooded outt b4.? or does it sound like somehow the injectors crapping out messed something else up? I am gonna get some more 93octane fuel and some good fuel system cleaner to try that in the morning. ugh..
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
This is what happens when backyard mechanics take things to a new level of stupid http://audiforums.com/forum/showthread.php?t=80267
A bit off topic but I thought u guys would get a kick outta this
A bit off topic but I thought u guys would get a kick outta this
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
I've heard good things about seafoam or is there something else that is better to get the junk that's probably stuck all thru the combustion chambers. I've also seen about spraying a small amount of water in to kinda steam clean things but it almost sounds like the sand idea from above!
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
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From: Johnstown, Pa
okay so after reading ingredients in seafoam that stuff ain't gonna do a damn thing. Isopropyl alcohol is about the strongest solvent in it. Guess i'll have to look into that berryman 3step system.
Thread Starter
Launching!
Joined: Aug 2012
Posts: 259
Likes: 0
From: Johnstown, Pa
i put some prestone fuel system cleaner in this video was about 15min or so of the car running after that. I pulled the fuel rails and put a bit of cleaner in the injector holes, and then the rest into the tank like your supposed too. It seems to idle well but as soon as I put the car into gear it sputters and misses terribly and smokes like a house fire or something. WTF is going on now is it possible there is just a bunch of crud in the combustion chambers? Or do ya think I toasted something?