Bad problems with engine dying, I'm out of town and need help
 

I have an LS3 crate 430 horse in a 61 Chevrolet bubble top. Booked up to a 4l65e. Harness and kit was purchased from PSI conversions, and I've been very happy with the kit so far and their support. I plan to call them on Monday but in the meantime hoping to get some feedback here.

I drove the car from St Augustine Florida all the way to Louisville, 610 mi, ran perfectly. Well here in Louisville fighting the rough roads the first night I had a couple times that it did a hesitation while driving it. oh boy, I think I'm going to have problems. And I am.

I can be driving along and it just all of a sudden dies and there are no codes in the engine. I pull over off the side of the road, put the foot on the brake and shut everything off (push button start, requires break shut off, requires brake to start), and then it just starts right back up and away I go. I might drive 2 miles and it does it again, I might drive 10 miles and it does it again.

So I figured this was a ground issue. I kind of traced back through how I had done my grounding and it was grounded like this: full size battery cablr, i(s that 1 ga), Anyway from the ground all the way up to the back of the head on the driver side. PCM grounds to the same spot. then there's a ground strap from the transmission to the frame.

Today I added a ground from the battery to the frame in the back, and from a header bolt to the frame in the front. I went to loosen the ground bolt on the head and tried to kind of scrape it up and found it was actually somewhat loose, not loose actually but very light effort to start unscrewing it. So I thought haha this thing was really the problem. I tightened it down well.

When I went to leave the fairgrounds it didn't want to start, finally started died two or three times leaving, died a couple times on the way to go eat. Went to leave the place to eat from I started it up backed up three feet and it died and it didn't want to start. Waited five minutes it started and I drove 23 miles to the hotel with no problems. My friend thought it sounded smoother as we were driving back. He's wondering if it needed to work something out so to speak after getting the grand strip set up. I have no faith in that.

I'm in Loisville, and have no idea who to check with. I plan to check up at the NSRS Nationals folks and see if they have anybody they can recommend that I could go to. It shows no codes on the engine I even hooked my code reader to it and definitely no codes. What I'm hoping is that I can find a good tuner here who can hook up to the computer and ride with me and see what is happening when it fails while he's with me. Of course that depends on if it actually does fail again. It has been failing faithfully until I put the grounds on, and then other than the initial failures it's ran that 23 miles back to the hotel, make me wonder if I can get it to fail with the tuner.

Sorry for the long post, would love to hear your thoughts. Also if you have any recommendations on who maybe could do that tuner hookup in Louisville I'd love to hear that. Or you may tell me that that wouldn't even work and they couldn't tell anyway

Thanks for reading...

Sounds like a power / poor grounding issue to me. Hopefully now you have it sorted.

I agree with Gofast, it sounds like something is loose somewhere. Since you've checked the grounds, I would start checking the power. Check for loose terminals at the main ignition relay and the ignition switch. Try wiggling wires around with it running to get it to loose power or shut off. If it isnt throwing any codes, then a tuner likley isnt going to be any help , at least from a diagnostic point of view. Intermittent problems are the worst kind to track down, but if you're diligent eventually you will find the root cause of the problem. Just to be clear, when it shuts off, it's like the key is just turned off, and not like it runs out of gas, right? That would basically eliminate the fuel pump side of the wiring. Good luck with it, I know how frustrating it can be having problems so far away from home, been there myself.

I appreciate the replies. I didn't know if I get something this week on the weekend.

Sounds like my thinking. I'm relatively certain now that it's not just the ground. All the bumps around here is what's caused all the problems to come to the forefront.

I just drove 26 miles back in to Cracker Barrel to eat breakfast, and no problems. I'm tempted to start up the road rather than spend the night here given that probably tuners aren't going to help me. I'll ust be prepared to stop overnight somewhere else.

While the intermittence is an annoyance, the fact that it starts up pretty much every time after it stops means I might be able to limp home.

I will post bacc learn how it goes.

One more question regarding using a tuner. would it not recognize if 12 volts went away which would definitely prove the thought of losing power?

What's your Voltage readings? I've had an issue with mine once, Weak battery. The starter would turn but engine wouldn't start. Found out that if Computer doesn't see 12v, it will not work. maybe your voltage is fluxing for some reason

I’d attack this situation by getting the car started and while it’s running start wiggling the harness every few inches end to end, wiggling/tapping ecu etc...and see if it shuts off. don’t overthink it just yet, it’s usually stupid little stuff... good luck man

Its most lilely a loose wire, or the ign relay is going out when hot. Thts why it most likely does better when cold.

Take the ign relay out and check for hot spots on the prongs. Make sure its getting a good 12v with key on. Before goin on road trip i would jump a temporary wire to it just to make sure.

I am in New Albany and can come and look at it if you need another set of eyes. I don't have tools or a garage, but I am willing to help. Sending you a PM with my number.

Andrew

Roger texted me and told me that he decided to limp it home. He will update later. So far, minor issues. Wish him the best!!!

Andrew

Check the 12 volt constant and the 12 volt switched connections at the fuse block. I had a issue with the 12 volt constant fuse spade contacting the connector and the engine would just shut off intermittently. Drove me crazy until as suggested above wiggling wires caused the engine to quit. Hope you make it home OK.

Pulling for a safe and speedy trip home.....and in for the updates.

class act right there ^^^^^^^^^

Got THAT right! Very nice of you Andrew!

Yes, Andrew was definitely stepping up! I contacted him as soon as I saw the message, to let him know I had already left town.

Everyone, I'm really appreciating the replies. It'll give me things to chase down the problem. I have driven to just south of Atlanta, and going to stop here and spend the night and then head on home tomorrow.

fortunately I only had it stopped once on the trip in just as I was going into Nashville. Hopefully I'll be as fortunate tomorrow.

once I get home with it I'm not sure how long I'll be getting into it and trying to chase the problem down, but I will keep it updated here on status.

Thanks again.

Quick update of note colon. When the engine dies the engine light does not come on. I'm thinking that points to a particular problem, but not sure what. Maybe that in fact it's lost 12 volts?

Another item in the chain of evaluation is the fact that I have a push button start. So the 'ignition switch" is within that system. Gofast... Maybe this is a reason to not consider installing push button start. of course I'm not saying the push button start is my problem, but we'll

FYI ... I've started out this morning to head home, got over into a parking lot and I'm in the middle of the parking lot with it having died and so far I can't get it started. I guess this is better than in the middle of the highway.

You don’t have one of those cheap Autozone type push button starters do you ???? If so I’d check that real quick, heard some horror stories about them

The push button start definitely adds another possibility. Is there a way you can jump the back of it, or in other words, hotwire it? Also, as another person mentioned, you may try removing the ignition relay and jumping the terminals in it to see if it stays running. You will have to remove the jumper to shut it off, but it may keep it running so you can get home.

No, he actually has a very nice push to start system. I think the cheapest thing (least expensive) on this car is the gas or maybe the air in the tires. Haha! Literally everything on this car is quality.


Wish I lived closer, all you would need to do is call and I'd be there helping you diagnose this in a heartbeat.
By the way, how is your progress?

Sounds to me like some intermittent problem with a hot lead or a critical ground. If the ECU or sensors were not happy there'd be evidence of that in the stored codes. Hope he makes it home safely and can get things sorted out.