My misery
Thread Starter
Instructor
Joined: May 2009
Posts: 110
Likes: 1
My misery
Hey guys I have a 93 40thann. lt1 that i just got back from my mech. who installed my msd dist. & coil, new water pump,harmonic balancer.Last fall i had a dealership replace plugs & wires (platnum plugs) and purged my injectors,fuel filter.(NEVER GO BACK TO A DEALERSHIP AGAIN) Anyway I just put on a new MAP,ECT,SENSORS,ECM. Ran the car till it was sputtering out of gas then filled with fresh. Only premium gas and moble 1 . ever since i've owned it.(2 yrs now) Anyway- It all started with bad opti ,got it back from mech. 2weeks ago ran fine for about 2 weeks I put a stage 2 chip in it ran fine for two days then it started taking longer and longer to start in the mornings.It also stumbles on acceleration.It will spit and sputter until i release the throttle,knocks like its out of time to. He put on the scanner no codes!!! but the MAP sens. is putting out 500volts or ohmes whatever is supposed to come out of there(elecricaly challenged)! Its supposed to be 5 or .5 not 500!
Fuel press. ok vacume tested ok to.
Fuel press. ok vacume tested ok to.
Racer
Joined: Jul 2005
Posts: 387
Likes: 3
From: Indian Trail, NC
what "stage 2" chip do you have in it right now? at this point, i think that may be the cause of the issue. you got it back running properly and then installed this chip and now it all went in the garbage. if you're looking for a good chip tuner that can meet your exact needs, go for PCMFORLESS. talk to Alvin...
Thread Starter
Instructor
Joined: May 2009
Posts: 110
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It's a hypertech chip . It came with the car uninstalled.I went to there web sight ,numbers mach its the right one for my car. It ran fine for 2 days after install.I changed ecm & removed chip as soon as it started acting up. 
THE guy who sold me the car told me its a stage 2
THE guy who sold me the car told me its a stage 2
Last edited by demon seed; May 17, 2009 at 11:54 PM.
Pro
Joined: Jan 2008
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From: Near Lockport NY Black 1986 Coupe
Drifting
Joined: Nov 2005
Posts: 1,324
Likes: 5
From: Charlotte NC
You might also want to pull your MAP and check the seal. I had crappy performance that I could never track down when a buddy mentioned checking the seal on my MAP. Sure enough, the last owner pancaked one side of the seal and the MAP must have been pulling atmosphere.
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From: altered state
St. Jude Donor '05
Drifting
Joined: Sep 2002
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From: Suwanee,Ga
Hey guys I have a 93 40thann. lt1 that i just got back from my mech. who installed my msd dist. & coil, new water pump,harmonic balancer.Last fall i had a dealership replace plugs & wires (platnum plugs) and purged my injectors,fuel filter.(NEVER GO BACK TO A DEALERSHIP AGAIN) Anyway I just put on a new MAP,ECT,SENSORS,ECM. Ran the car till it was sputtering out of gas then filled with fresh. Only premium gas and moble 1 . ever since i've owned it.(2 yrs now) Anyway- It all started with bad opti ,got it back from mech. 2weeks ago ran fine for about 2 weeks I put a stage 2 chip in it ran fine for two days then it started taking longer and longer to start in the mornings.It also stumbles on acceleration.It will spit and sputter until i release the throttle,knocks like its out of time to. He put on the scanner no codes!!! but the MAP sens. is putting out 500volts or ohmes whatever is supposed to come out of there(elecricaly challenged)! Its supposed to be 5 or .5 not 500! Fuel press. ok vacume tested ok to.
Fuel press. ok vacume tested ok to.I'd check the dist. & see if is not a tooth or two off. Can happen and it's pretty common theses days.
TJM
Racer
Joined: Jul 2005
Posts: 387
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From: Indian Trail, NC
Drifting
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From: 1994 LT1 Coupe 6-speed with FX3 & 2000 LS1 Vert 6-Speed with F45 Hunterdon County, NJ
Le Mans Master
Joined: Jan 2006
Posts: 5,621
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From: Orlando FL
Being off just 2 teeth the car would probably never start much less run bad. I would go back to square 1 and put the original chip back in. I would like to see a scan to see what the fuel trim numbers are to make sure mixture is right. Your symptoms have a few signs of a bad opti. Just a thought to keep in the back of your mind.
I would also take a look at fuel pressure on start and run to see if that is any factor.
Thread Starter
Instructor
Joined: May 2009
Posts: 110
Likes: 1
thanx for the advice, I think its the opticrap to , Im just hopeing it was something else.(something cheaper) As i dont have a place to tear my car apart. I will try a few more little things before taking back to mechanic. Since the MSD dist is brand new (less than 100k's on it) those PEOPLE (trying my hardest not to swear) should pay for the labour for this fun job. 800-1000 dollars
.I know this will never happen just bieing sarcastic. I used to think msd was the shizz. anyone know of a different aftermarket dist. I mean one better than stock.
:bea tdeadhorse: OH yeah for the other guy (I did take out that chip the first sign of trouble, and replaced ecm also) thanx again guys
.I know this will never happen just bieing sarcastic. I used to think msd was the shizz. anyone know of a different aftermarket dist. I mean one better than stock.:bea tdeadhorse: OH yeah for the other guy (I did take out that chip the first sign of trouble, and replaced ecm also) thanx again guys
Thread Starter
Instructor
Joined: May 2009
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UPDATE- just finnished installing jons fic injectors .....piece of **** still wont start must be something else I read in this (common problems) thingie that wile trying to start, the engine will stumble like its trying to start when you release the key back to the run poossition. thay said it is a poor or insufficant power supply to ignition. 
Dose this sound possible , has it happened to anyone else. where would a guy look to inspect these wires. Hell it could just be the ground .
must be something else I read in this (common problems) thingie that wile trying to start, the engine will stumble like its trying to start when you release the key back to the run poossition. thay said it is a poor or insufficant power supply to ignition. Dose this sound possible , has it happened to anyone else. where would a guy look to inspect these wires. Hell it could just be the ground .
Melting Slicks
Joined: Jan 2009
Posts: 3,482
Likes: 196
From: folsom california
always try the five dollar solution begore you try the fifty (or five hundred) dollar solution.
If your engine wants to start, but dies, or runs crappy, when you release the key, try relacing the oil pressure safety switch.
this switch is designed to shut off power to the fuel pump if the oil pressure fails. In an accident, if the engine stopped but the ignition remained on, this safety switch prevents power from flowing to the fuel pump. The switch is bypassed when the starter is engaged, allowing fuel to the engine during starting.
this switch typically fails because old oil and carbon gum up its oil side or the contacts simply begin to go bad and get progressively worse.
the switch is located on the back, top of the engine next to the firewall. There are actually two units, the one with a single wire is the oil pressure sending unit, the one with muliple wires is the oil pressure safety switch.
I think the cost of the safety switch is around $20; maybe (probably) a little more.
regardless of cost, replacement of this switch is good insurance; the original will not last forever.
best of luck, please keep us posted on your progress.
If your engine wants to start, but dies, or runs crappy, when you release the key, try relacing the oil pressure safety switch.
this switch is designed to shut off power to the fuel pump if the oil pressure fails. In an accident, if the engine stopped but the ignition remained on, this safety switch prevents power from flowing to the fuel pump. The switch is bypassed when the starter is engaged, allowing fuel to the engine during starting.
this switch typically fails because old oil and carbon gum up its oil side or the contacts simply begin to go bad and get progressively worse.
the switch is located on the back, top of the engine next to the firewall. There are actually two units, the one with a single wire is the oil pressure sending unit, the one with muliple wires is the oil pressure safety switch.
I think the cost of the safety switch is around $20; maybe (probably) a little more.
regardless of cost, replacement of this switch is good insurance; the original will not last forever.
best of luck, please keep us posted on your progress.
Melting Slicks
Joined: Oct 2006
Posts: 2,238
Likes: 10
From: College Station TX
always try the five dollar solution begore you try the fifty (or five hundred) dollar solution.
If your engine wants to start, but dies, or runs crappy, when you release the key, try relacing the oil pressure safety switch.
this switch is designed to shut off power to the fuel pump if the oil pressure fails. In an accident, if the engine stopped but the ignition remained on, this safety switch prevents power from flowing to the fuel pump. The switch is bypassed when the starter is engaged, allowing fuel to the engine during starting.
this switch typically fails because old oil and carbon gum up its oil side or the contacts simply begin to go bad and get progressively worse.
the switch is located on the back, top of the engine next to the firewall. There are actually two units, the one with a single wire is the oil pressure sending unit, the one with muliple wires is the oil pressure safety switch.
I think the cost of the safety switch is around $20; maybe (probably) a little more.
regardless of cost, replacement of this switch is good insurance; the original will not last forever.
best of luck, please keep us posted on your progress.
If your engine wants to start, but dies, or runs crappy, when you release the key, try relacing the oil pressure safety switch.
this switch is designed to shut off power to the fuel pump if the oil pressure fails. In an accident, if the engine stopped but the ignition remained on, this safety switch prevents power from flowing to the fuel pump. The switch is bypassed when the starter is engaged, allowing fuel to the engine during starting.
this switch typically fails because old oil and carbon gum up its oil side or the contacts simply begin to go bad and get progressively worse.
the switch is located on the back, top of the engine next to the firewall. There are actually two units, the one with a single wire is the oil pressure sending unit, the one with muliple wires is the oil pressure safety switch.
I think the cost of the safety switch is around $20; maybe (probably) a little more.
regardless of cost, replacement of this switch is good insurance; the original will not last forever.
best of luck, please keep us posted on your progress.