This 55 Chevy is cutting off while driving down road and you have to crank with key to get it running again.You can't leave it in run on key and let clutch out to refire it won't do it until to crank with key.Doesn't do it all the time just sometime.Have changed the coil and dist pickup and now the complete dist.It has TPI on it and have had the car since 74 but put TPI on it in 93 or so just started this in the last year.No codes on computer.It will buck and acts like no fuel but you should be able to crank without cranking with key only.About to dive me crazy.Thought it might be the old Super Sun Tack but it has been in the car since 74 clipped the wire to coil and no good. Though I had fixed it but the cutting off came back..Thanks for any help.
The ignition switch? Just a thought but maybe the switch is going bad. Maybe why you have to use the key to start it. A bump jostling the switch around and that's why it wont work with the clutch. It might be cycling to the off position. Do any of your accessories wired to the switch still work when it cuts off?
Is fuel getting cut off - filter in the system, fuel pump sock, weak fuel pump. Low fuel pressure will cause injector firing issues with TPI. If you Dont have a fuel filter in the system you injectors may be clogged. Since this is tpi based, the thread won't last long, hope you get it worked out.
Replaced fuel filter a couple times.When running it is always smooth then all of a sudden buck and buck the may cut off or smooth out or cut off.Then have to cycle key to off and crank and it runs.Have taken tank out a few times but it is clean.Have 45 psi on fuel rail gauge but can't see gauge when it does it.Started this about 6 month or so ago.May change pump since the 35 I working on now will have another TPI in it .If that does'nt fix it I still need a pump for that one..Have 3 cars with them.Thank ya'll for info
Most/all FI engine fuel systems run the fuel pump for 2 or 3 seconds when the switch is turned on to pressurize the system during start up. If the computer 'sees' evidence the engine is running, the pump will be energized to keep it running. If their is no 'running signal' the pump will not be energized. This is for safety's sake in the event if a broken fuel line or vehicle accident. What I am suggesting as a possibility in your case is that, whatever the reason for the initial engine losing power may be, the fuel system may be "turned off" by the computer, for the reason described above, and will not energize the fuel pump until the key start process again runs the pump. So, if that theory is valid, that would explain half your problem. But that still leaves the challenge of finding the underlying issue as to what is the engine to stumble and die in the first place. Fuel, fire and air......the engine runs. Good luck with tracking down which of the first two is the culprit. Ray
This has nothing to do with helping you with your problem but might help someone with a similar problem. I saw a friend sitting on the side of the road last night on the way home from a cruise-in and I stopped to see if I could help,we were checking the normal things and purely by accident I pulled the hot wire to the coil and it slid of the terminal,it had a u connector and wasn't tight. He had just driven to Knoxville,Tennessee and back earlier this month without any problem. HRP
It may be loosing the RPM signal. That would stop the pump from running. If you have a fuel pressure gauge connect it to the fuel rail and tape it to the windshield so you can see fuel pressure while driving.
If you have an aftermarket ign. switch like Danchuck. Try to find one on eBay NOS. as stated before do you have a large key ring.
Looking at third gen forums, these seem to stem from ignition module (you've already replaced) weak fuel pump or fuel pump ground, or faulty injector that causes incorrect signal and the injectors stop firing. How are you setting them up in your cars? Cut down factory harness and factory ECM? I've got a 350 tpi from 89 formula with all electricals, I was going to use it in a swap that never worked out. Just curious.
I had a 350 engine that did the exact same thing. After spending a lot of money changing plugs and wires and vacuum lines I finally decided to put in a new distributor and it still did it!!!! I good friend of mine told me to try a quart of Marvel Mystery Oil which I did and never had the problem again. A lifter was hanging up from time to time and made it feel just like someone had pulled a plug wire off. I would have sworn it was an electrical problem but I was wrong. Jimbo
Thanks I put it on lift yesterday and it almost quit will start checking things out.The car seemed to lean out when it caught back up.You could hear engine sucking air.Have a modified GM harness but been driving it since early 90's with this TPI.Will change pump and I'll put fuel gauge on it today before I change pump.Drove other car with TPI yesterday and ran fine.Thanks for help
These had a molded plug for coil to go to computer and to hot lead Thanks.Ran it yesterday in garage and it would not stumble or anything.Hate it when it dies it when it wants to.Will keep chasing it.Going to clean all grounds
If ecm bad would not run at all or give fault code.Changed hei and coil.Resanded grounds last night will try today to run it.Ran it in garage for 20 minutes last night but has done this before so will get it out and go for a ride today
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