Mysterious Problem

[91mrtoo]

My mother seems to have broken my car.

Symptom: She was driving on the highway and noticed the car was slowing. She pushed on the accelerator and nothing happened. The engine was not running and she was unable to start the car from the side of the road.


I initially though of the timing belt when I was talking to my mom, but that doesn't make sense due to the fact that it is sparking on all 4 of the plugs. Here is how I have tried to diagnose the problem.


What I have checked:
Spark: I get spark on all 4 plugs, checked by taking the plugs out. I have also taken the main lead off the distributor cap and I can get the spark from that to jump about 1/2" to the block. It looks very strong.


Fuel Pump: I can hear it running when starting, but I also shorted it on using the diagnostic connector. I can pinch the return line and the noise changes pitch, so I assume that there is fuel present in the line.

Inject: I smell gasoline in the exhaust. I can hear the injector firing by putting a screwdriver against it and the other end against my ear.

It seems odd to me if I have spark and inject the car wouldn't be even trying to start. Any ideas on what else I can check? Any mistakes I have made in diagnosing? I am going to check timing tomorrow when I go back to see the car (it is an hour away), but after that, I am mystified as what else might be wrong. It just seems odd that the car would be running fine and then all of a sudden stop.

[PearlJammzz]

could be timing, you'd still get spark and fuel but nothing would be burning so you'd smell a **** ton of gas.

[Dance_Business]

Is it a turbo? Sounds like mine when I blew a coupler off.

[91mrtoo]

What would cause timing to all of a sudden be off? That is what confuses me.

[91mrtoo]

No Turbo. This is a 91 5-SFE with the manual transmission. Approx 170,000 miles.

[muffinman]

Originally Posted by 91mrtoo

What would cause timing to all of a sudden be off? That is what confuses me.

possibly belt jumped a tooth or broke

[Gairloch]

If your distributor is loose that could have rotated and thrown the timing off also.

Can you give us a more precise description of your symptoms? What happens when you try to start the car?

[91mrtoo]

I really don't have any more specific symptoms to give. The car will currently crank over just fine, but will not catch at all. The distributor is not loose enough for me to be able to rotate it by hand. I can get spark on all four plugs, which means the distributor is rotating, so I don't think that the timing belt is broken, as the distributor must be rotating for this to occur. Everything else I know relating to inject, fuel pressure, and spark should be detailed in the first post.

[Gairloch]

Engine needs 4 things to run:

1. Air
2. Fuel
3. Spark
4. Compression

(I'm sure you know this, documenting for posterity. )

You have spark, air and fuel. Next step I would take is to do a compression test.

When you pulled the plugs did they look like they were in good shape?

[bumpstickboogie]

Originally Posted by 91mrtoo

I really don't have any more specific symptoms to give. The car will currently crank over just fine, but will not catch at all. The distributor is not loose enough for me to be able to rotate it by hand. I can get spark on all four plugs, which means the distributor is rotating, so I don't think that the timing belt is broken, as the distributor must be rotating for this to occur. Everything else I know relating to inject, fuel pressure, and spark should be detailed in the first post.

the distributor rotates from the cam right, if so then it would still rotate with a broken timing belt. luckily the 5sfe is a non interference engine so you'd be in luck if that's the problem and would only have to replace the belt.

[Gairloch]

If the timing belt is broken then the cams, thus the distributor, ain't gonna turn no-how