Why would a car run perfect, until you try to restart it?

[JC316]

Hey guys, I have a tough problem.

I picked up a 1998 Altima with an oil leak. The timing chain ate through the guide and into the front cover. While diagnosing the oil leak, the car just randomly died on me. It was on empty, so I figured it was out of gas. I added more and it fired back up with no issue. I went through the engine and changed the timing chains, guides, tensioners, and oil pump. Got it all back together and it fired right up and drove perfectly.

Here is where things start to get weird, I started it up and moved it, then I killed the engine. When I tried to restart it, it would just crank, but not fire. I cycled the key on and off a few times and it fired right back up. Drove it down to the store, killed it, got back in the car and it fired up, but died within 3 seconds. Same story as before, cycle the key and fire it back up. Got it home, fixed a couple of ground wires, drove it 14 miles without a problem, but again when I kill it and try to restart, it fires, then dies immediately, but this time, it won't stay started, just keeps catching and then dieing within 3 seconds..

Did some digging, figured that it had oil in the distributor, so I took the dizzy apart, but found it to be clean. Found a lot of corrosion on the cap terminals and rotor, so I cleaned it off and put it back together. Tried to start it, which it did, but I am backfiring through the intake and then it dies. Figured that I caused it when I cleaned the corrosion off, so I went and got a new cap, rotor, and wire set, put it all on and now it wont start at all.

I have spark and fuel pressure, no codes, no warning lights. The timing was set perfectly and I never got an indication that the timing jumped.

[SC457A]

Simple rule of thumb. Fuel at proper amount and timing, proper compression, and good spark at proper timing. Yes everyone knows this here.

Start basics and move up. I knew a Pro Mod team that could not get the race car to start. It was out of fuel.

I would start fuel system. An old tech told me once. "The fuel pumps on them electric things can play tricks on ya." Damn I miss him.

[JC316]

Simple rule of thumb. Fuel at proper amount and timing, proper compression, and good spark at proper timing. Yes everyone knows this here.

Start basics and move up. I knew a Pro Mod team that could not get the race car to start. It was out of fuel.

I would start fuel system. An old tech told me once. "The fuel pumps on them electric things can play tricks on ya." Damn I miss him.

Yeah, but common wisdom goes out the window when a car runs great until you kill it. That is the unique element here, why does it run fine until it's turned off? Even still, I am going through the motions just in case.

[TexasT]

Fuel pressure regulator. Or possibly a leaky injector that is flooding the engine.

Does it hold pressure when you turn the key to prime the pump? Then turn the key to off, does the pressure hold steady?

How about fuel filter? How old? More than 10k or unknown I'd go with a fresh one.

[shumpertdavid]

Welcome to auto repair. There's literally hundreds of potential causes to your problem. As stated before, go back to the basics. You say it has spark, is that through a spark plug or using a screw driver, if so invest a few dollars into a HEI ignition tester. It looks like a spark plug with a ground clip, no electrode or ground tang. It forces the coil to produce peak spark (@50k volts) to jump the gap, if it won't jump it or has a lot of inconsistency then you could have a weak coil. You need a hot bluish white spark. Second is fuel pressure, you need a gauge to adequately test it, just seeing that it has fuel pushing out of the line is not sufficient, also volume is an important factor, it should make a pint in 30 seconds on free flow. Injector pulse should be checked too, a cheap set of noid lights will generally cover this.

As far as running great and then not restarting, cam and crank sensors can do this from heat soak. I'm not saying that's your problem, but it's a common general type failure I've seen over the years. Some cars will continue to run if it looses the signal after start up, but will not start if it doesn't generate the signal during cranking. There's a lot of variables.

[JC316]

Fuel pressure regulator. Or possibly a leaky injector that is flooding the engine.

Does it hold pressure when you turn the key to prime the pump? Then turn the key to off, does the pressure hold steady?

How about fuel filter? How old? More than 10k or unknown I'd go with a fresh one.

It holds pressure, but it doesn't have a port, so you have to disconnect one of the lines going to the fuel rail. FPR is on my hit list. Fuel filter is unknown, but since it had original wires at 264K miles, I would say that it's likely never been changed. I will change it, but I doubt that it's my main problem.

Welcome to auto repair. There's literally hundreds of potential causes to your problem. As stated before, go back to the basics. You say it has spark, is that through a spark plug or using a screw driver, if so invest a few dollars into a HEI ignition tester. It looks like a spark plug with a ground clip, no electrode or ground tang. It forces the coil to produce peak spark (@50k volts) to jump the gap, if it won't jump it or has a lot of inconsistency then you could have a weak coil. You need a hot bluish white spark. Second is fuel pressure, you need a gauge to adequately test it, just seeing that it has fuel pushing out of the line is not sufficient, also volume is an important factor, it should make a pint in 30 seconds on free flow. Injector pulse should be checked too, a cheap set of noid lights will generally cover this.

As far as running great and then not restarting, cam and crank sensors can do this from heat soak. I'm not saying that's your problem, but it's a common general type failure I've seen over the years. Some cars will continue to run if it looses the signal after start up, but will not start if it doesn't generate the signal during cranking. There's a lot of variables.

Oh I know. Cam/crank sensor, coil, MAF, IAT, ECT, TPS, and a half dozen more can cause symptoms like this, but I can't afford to just blindly throw parts. Tested spark with an inline spark tester. Will go through the basics today.

[46Tbird]

Just based on what you typed, I would assume the fuel pump took a dump. Every symptom is exactly what I would expect. Put a pressure gauge on it and see what ya got.

[JC316]

Just based on what you typed, I would assume the fuel pump took a dump. Every symptom is exactly what I would expect. Put a pressure gauge on it and see what ya got.

We have a winner. Tried to start it today and the pump didn't prime. Checked the fuse, relay, then for power at the pump, all good. Will report back once I get pump changed out.

[JC316]

Got it. Was the fucking relay. Tricky little bastard. It showed power when the harness was apart, but when I connected the harness to the pump, it drained all power. Swapped it out and the car runs great.

[SC457A]

And people bitch of auto repairs costs.

Glad you found problem.

[Sleeper]

I was about to say fuel pump or clogged cat.

[JC316]

And people bitch of auto repairs costs.

Glad you found problem.

Lol, yeah. Took me 5 hours of tracking to find the damned thing, then 5 seconds to get it fixed. I hate intermittent failure. One thing that took so long is the misinformation out there on this car. Like the location of the fuel pump relay. It's not marked and the internet says it's the top right relay, the FSM says it's the bottom left relay and it's actually the top left.

[crapstang]

I was about to say fuel pump or clogged cat.

Fuel pump was my guess. Those turds fail all of the time it seems like. Fuck in-tank pumps!