350 tpi will start but won't stay on

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Dec 1, 2014 | 12:11 PM
  #1  
I just switched from a 305tbi to a tpi350 in My 88 camaro ...car will start but won't stay on...any suggestions ?
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Dec 1, 2014 | 12:19 PM
  #2  
Dumb question but did you change the fuel pumps? TBI uses 13psi and tpi uses 43psi.
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Dec 1, 2014 | 12:25 PM
  #3  
Re: 350 tpi will start but won't stay on
Quote: Dumb question but did you change the fuel pumps? TBI uses 13psi and tpi uses 43psi.
Yes I changed the fuel pump ...
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Dec 1, 2014 | 12:28 PM
  #4  
That's why its a dumb question. How's it run when its running? What was changed? Any codes? The usual questions
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Dec 1, 2014 | 12:35 PM
  #5  
Re: 350 tpi will start but won't stay on
Quote: That's why its a dumb question. How's it run when its running? What was changed? Any codes? The usual questions
Lol yea I'm new to this...well it fires right up ...and as it starts to idle it just cuts right off ...just changed the motor, ECM nd wiring harness nd fuel pump nd switch the battery from left side to the right side
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Dec 1, 2014 | 12:36 PM
  #6  
What year ecm? Speed density or maf system? What you describe is vats turning off fuel since it has no signal or wrong signal.
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Dec 1, 2014 | 12:42 PM
  #7  
Re: 350 tpi will start but won't stay on
Quote: What year ecm? Speed density or maf system? What you describe is vats turning off fuel since it has no signal or wrong signal.
Uuuuhhn I'm not sure actually lol...but it was a 89 gta
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Dec 1, 2014 | 12:44 PM
  #8  
Re: 350 tpi will start but won't stay on
Quote: What year ecm? Speed density or maf system? What you describe is vats turning off fuel since it has no signal or wrong signal.
If it is the Vats turning off fuel ..how would I be able to fix that and get her back running ?
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Dec 1, 2014 | 12:44 PM
  #9  
First year. Look up vats wiring. You need it or bypass it in the chip. The wiring won't be in your dash harness but you could add it I think. If the donor car is available swap the dash harness and vats module. If not you'll have to get a chip written without vats
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Dec 1, 2014 | 12:48 PM
  #10  
Re: 350 tpi will start but won't stay on
Quote: First year. Look up vats wiring. You need it or bypass it in the chip. The wiring won't be in your dash harness but you could add it I think. If the donor car is available swap the dash harness and vats module. If not you'll have to get a chip written without vats
Oooohh ok thanks bro ...and if it's not the Vats anything else it be ...
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Dec 1, 2014 | 12:51 PM
  #11  
Had to say since it starts and shuts right off I assume within 3 seconds?
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Dec 1, 2014 | 12:54 PM
  #12  
Re: 350 tpi will start but won't stay on
Quote: First year. Look up vats wiring. You need it or bypass it in the chip. The wiring won't be in your dash harness but you could add it I think. If the donor car is available swap the dash harness and vats module. If not you'll have to get a chip written without vats
Would I be able to get wiring from 89 camaro also ?and were would I be able to get chip written without Vats...would it be better to do the wiring or chip or it doesn't matter ?
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Dec 1, 2014 | 12:55 PM
  #13  
Re: 350 tpi will start but won't stay on
Quote: Had to say since it starts and shuts right off I assume within 3 seconds?
Yea something like that ...
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Dec 1, 2014 | 12:57 PM
  #14  
If the wiring is their from a donor is just swap dash harnesses. Steering column included. Read up on the vats before you choose
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Dec 1, 2014 | 01:02 PM
  #15  
Re: 350 tpi will start but won't stay on
Quote: If the wiring is their from a donor is just swap dash harnesses. Steering column included. Read up on the vats before you choose
Ooh ok ...well I don't have the donor anymore ...I'll have to go hunt ...
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Dec 1, 2014 | 01:03 PM
  #16  
Look up companies then to write a chip without vats. It'll be a day or so out but it'll prevent any further hassle I'd think
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Dec 1, 2014 | 08:12 PM
  #17  
Re: 350 tpi will start but won't stay on
Are you getting any codes? When I installed new fuel pump after upgrading engine to 355cc, I had a code (56?) for low voltage to fuel pump.

Timing might be an issue; mine is 11 degrees cold start, not zero as the shop manual says.

Am about to reprogram LPROM, to keep cold engine from running rich. My spark plugs are fouling.
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Dec 1, 2014 | 09:44 PM
  #18  
Re: 350 tpi will start but won't stay on
Is the oil pressure sender hooked up?

Stretching my brain here to remember but didn't the ECM turn off fuel if it didn't detect oil pressure at the sender on some years?
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Dec 1, 2014 | 10:33 PM
  #19  
Not the 89. I had that system swapped. It will kill the pump tho almost immediately. The fuel pump relay powers the pump for the initial cranking then the oil sensor switch kicks in
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Dec 1, 2014 | 10:38 PM
  #20  
Re: 350 tpi will start but won't stay on
I just pulled up the 1989 5.7L TPI wiring. It has a oil pressure switch wired to the fuel system. So the 89 does have a cut-off if there is a lack of oil pressure.

350 tpi will start but won't stay on-1989-5.7l-tpi-engine  

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Dec 1, 2014 | 10:45 PM
  #21  
Which if you read what I said I agreed. It doesn't power down the ecm which you sorta asked/mentioned. I have that diagram imbedded into my head as I spent a number of hours putting an 89tpi in my 91 TBI equipped car at one point.
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Dec 1, 2014 | 10:46 PM
  #22  
Re: 350 tpi will start but won't stay on
Quote: Which if you read what I said I agreed. It doesn't power down the ecm which you sorta asked/mentioned. I have that diagram imbedded into my head as I spent a number of hours putting an 89tpi in my 91 TBI equipped car at one point.
Never said it powered the ECM down, just that it shut down the fuel pump.

It may be related to the OP's problem.
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Dec 1, 2014 | 10:47 PM
  #23  
Quote: Is the oil pressure sender hooked up?

Stretching my brain here to remember but didn't the ECM turn off fuel if it didn't detect oil pressure at the sender on some years?
Ecm turn off the fuel would make you think that man. I'm not trying to pick a fight, that's counter productive to the OP. Also I wasn't clear in my response back. I referenced that the ops shuts down the ecm so I apologize
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Dec 1, 2014 | 10:51 PM
  #24  
I agree the ops very well could be the issue. That's why I love these forums, every single one of us has ran into an issue at some point so we all drop an idea.
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Dec 2, 2014 | 03:21 AM
  #25  
Re: 350 tpi will start but won't stay on
Quote: Are you getting any codes? When I installed new fuel pump after upgrading engine to 355cc, I had a code (56?) for low voltage to fuel pump.

Timing might be an issue; mine is 11 degrees cold start, not zero as the shop manual says.

Am about to reprogram LPROM, to keep cold engine from running rich. My spark plugs are fouling.
I'm lost ..this is my first time doing any kinda work to a car myself ...and I didn't even do it by myself ...I had help lots of it ...but I'll look in to that ...everyone's been telling it's most likely vats ..just tryn to get a good idea what it could be ...thanks
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Dec 2, 2014 | 05:30 AM
  #26  
Re: 350 tpi will start but won't stay on
idk a lot about the vats ... but i do know when i swapped from tbi 305 to carbed 350 before, i had (almost) the same problem pump would shut off from not seeing the oil pressure (put in a mech gauge). i would make it about a block. for sure, check the sending unit wires before going into all the vats trouble.
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Dec 2, 2014 | 09:03 AM
  #27  
Re: 350 tpi will start but won't stay on
Quote: I'm lost ..this is my first time doing any kinda work to a car myself ...and I didn't even do it by myself ...I had help lots of it ...but I'll look in to that ...everyone's been telling it's most likely vats ..just tryn to get a good idea what it could be ...thanks
Timing is less likely to be your problem. Your car is starting, then shutting off. It usually indicates a fueling issue.

VATS and the Oil Pressure Switch are the more likely culprit.

The ECM primes the pump for a second or two when you turn the key to the RUN position. Which pressurizes the rails and makes starting easier. This is usually enough for the engine to run for several seconds even if the fuel pump isn't running.

I can't remember if VATS disables the injectors from the get go if the right key is not found, or if the injectors are temporarily enabled enough to start the engine.

Its been some time since I had a TPI car.
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Dec 2, 2014 | 10:19 AM
  #28  
It disables the fuel pump and starting system. He doesn't have the wiring for vats so the starting system wouldn't be disabled. Only pointing that out*
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Dec 2, 2014 | 04:01 PM
  #29  
Re: 350 tpi will start but won't stay on
Summit sales a VATS bypass by Painless I think but I thought it was 90 and above.Oil pressure will do it but Vats will not run at all and it will give a code 46 but it has to be a 90 system I think.
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Dec 2, 2014 | 06:12 PM
  #30  
Vats started in 89. I have an 89 system and had to bypass it.

http://www.camarosource.ca/brochures...1989broch2.jpg
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Dec 3, 2014 | 08:59 PM
  #31  
Re: 350 tpi will start but won't stay on
Quote: idk a lot about the vats ... but i do know when i swapped from tbi 305 to carbed 350 before, i had (almost) the same problem pump would shut off from not seeing the oil pressure (put in a mech gauge). i would make it about a block. for sure, check the sending unit wires before going into all the vats trouble.
Ooh ok for sure I will make sure I checc ...thanks bro
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Dec 3, 2014 | 09:01 PM
  #32  
Re: 350 tpi will start but won't stay on
Quote: Timing is less likely to be your problem. Your car is starting, then shutting off. It usually indicates a fueling issue.

VATS and the Oil Pressure Switch are the more likely culprit.

The ECM primes the pump for a second or two when you turn the key to the RUN position. Which pressurizes the rails and makes starting easier. This is usually enough for the engine to run for several seconds even if the fuel pump isn't running.

I can't remember if VATS disables the injectors from the get go if the right key is not found, or if the injectors are temporarily enabled enough to start the engine.

Its been some time since I had a TPI car.
Ooh ok ..I will definitely checc oil pressure switch ... Thanks
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Dec 3, 2014 | 11:10 PM
  #33  
Check pickup coil in bottom of dizzy .. not the icm
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Dec 5, 2014 | 01:25 AM
  #34  
Re: 350 tpi will start but won't stay on
Well Imma order the " fix it security VATS bypass module "

And hopefully she works I'll post results after ....wish me luck 😁

http://m.ebay.com/itm/191421440383?nav=SEARCH
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Dec 5, 2014 | 06:11 AM
  #35  
Make sure you call them first and explain the swap you did. You do not have the wiring for vats and that may be a plug and play deal I.e; you may be stuck wiring the car for vats just to bypass it. Hate to say but you may have to just order a prom with vats removed.
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Dec 5, 2014 | 11:44 AM
  #36  
Re: 350 tpi will start but won't stay on
Quote: Make sure you call them first and explain the swap you did. You do not have the wiring for vats and that may be a plug and play deal I.e; you may be stuck wiring the car for vats just to bypass it. Hate to say but you may have to just order a prom with vats removed.
Yea I made sure I called them 1st they told me since car is starting that I should only need a fuel bypass but I oreder both for only $55.00 ...just in case ...question , since I will be bypassing how can I make sure car is not east to take/steal ?? Can I still put alarm system with out it being another problem ?
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Dec 5, 2014 | 11:49 AM
  #37  
Re: 350 tpi will start but won't stay on
Quote: Yea I made sure I called them 1st they told me since car is starting that I should only need a fuel bypass but I oreder both for only $55.00 ...just in case ...question , since I will be bypassing how can I make sure car is not east to take/steal ?? Can I still put alarm system with out it being another problem ?
Nothing you do will make the car hard to steal. These cars have been around for a while, there is only so much you can do. The methods for bypassing the theft deterrents are well known by thieves.
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Dec 5, 2014 | 11:53 AM
  #38  
I agree. It is a easy unfortunately. Hell I made my bypass using the dimmer module and a resistor. Sad but it works and I was stuck at that time with my soldering kit. Made up a unit and dialed in the resistance and yea.... I'm curious how the fuel bypass works? Does it send a 60hz signal to the computer?
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Dec 6, 2014 | 12:51 AM
  #39  
Re: 350 tpi will start but won't stay on
Quote: Nothing you do will make the car hard to steal. These cars have been around for a while, there is only so much you can do. The methods for bypassing the theft deterrents are well known by thieves.
Ooh ok I'll figure out something ... detachable steering wheel like the guys in the Hondas or something lol ...
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Dec 6, 2014 | 12:55 AM
  #40  
Re: 350 tpi will start but won't stay on
Quote: I agree. It is a easy unfortunately. Hell I made my bypass using the dimmer module and a resistor. Sad but it works and I was stuck at that time with my soldering kit. Made up a unit and dialed in the resistance and yea.... I'm curious how the fuel bypass works? Does it send a 60hz signal to the computer?
Uuuuhhnmm I'm not sure exactly soon as It gets here and I check everything out I'll let you know bro
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