Only starts when towed 93 manual

[2strokenut]

Took my 93 explorer manual out to the desert for some romping like I always do but something weird happened. On one run the engine died around 35 mph and then after a few seconds it started running like normal. I decided to slow down and do a damage check but it just died. It cranked over but no start. I checked fuel pressure, and let some out of the check valve. Pump also turns on. So we towed it back to camp and my buddies looked at it. We checked every fuse, vacuum line etc and nothing looksed to be out of place or burnt up. We hooked up a pressure gauge and pressure wouldnt register very high. Then we pulled the intake and sprayed starter fluid in and wouldn't ya know it fired right up but quickly died. We decided to just tow it home since we didn't bring an extra fuel pump.

On the way home downhill in 3rd I saw that the temp gauge was rising very slightly (when we left it was cold) and gave it a little gas, almost ran into my buddy towing me haha. I signaled him to pull over and as soon as we slowed and rpm's dropped around 1200 it died. It turned over but wouldn't start. SO we got going again this time I did not let it go below 1500. It stayed running ffor a few mintutes so it seemed alright. We pulled over again as I kept the idle up pulled off the tow strap and took off. While still on the downhill I let off the gas and as it got down around 1200 it would die. Luckily with a manual it started right back up. At every stop I had to just keep revving the engine but I made it home. Power seemed as good as ever but I'm stumped. Seems like something electrical or sensor related. Gonna take a look tomorrow but I've been searching for hours and kind find a similar thread.

Any ideas would be appreciated. We have another explorer so I think I'm going to start swapping the MAF and TPS sensors and even an IAC valve to eliminated those being the issue.

Thanks!

 

[briwayjones]

Clogged fuel filter? Dunno!

 

[FIND]

Sounds like a plugged fuel filter

 

[tgreene92]

agreed sounds like a clogged filter, however this situation is eerily similar to a problem my friends toyota had, he ended up having a faulty voltage regulator so the fuel pump would turn on and off when the voltage to the pump fluctuated. we didnt figure this out tho until we cleaned or replaced all the fuel lines, then went to start it up and realized the battery and alternator were fried.

 

[2strokenut]

Hmm sounds like I should replace the fuel filter tomorrow. Wouldnt I see the irregular voltage readings on the gauge?

 

[tgreene92]

yea but if the regulator is bad who knows what sensors, meters, gauges etc... are being screwed up..my buddy's yota would get like 11 volts then jump to 15 then back down to 11 but the gauge wasn't changing..i really doubt this is your problem i was just throwing it out there since they were very similar situations. if you want to be positive get a voltmeter and see what kind of voltage the batterys getting, should be right around 14 to 14.5. have you checked your fuel injectors a few of them could be dirty or damaged? how long was the truck running for before this happened?

 

[2strokenut]

yea but if the regulator is bad who knows what sensors, meters, gauges etc... are being screwed up..my buddy's yota would get like 11 volts then jump to 15 then back down to 11 but the gauge wasn't changing..i really doubt this is your problem i was just throwing it out there since they were very similar situations. if you want to be positive get a voltmeter and see what kind of voltage the batterys getting, should be right around 14 to 14.5. have you checked your fuel injectors a few of them could be dirty or damaged? how long was the truck running for before this happened?

The truck has been running excellent since the day I bought it, about 2 months ago. It was running crazy good right up until it just died and started up again. I was hitting some fairly big whoops at the time I originally thought I may have just ripped a wire out of something or broke the pump.

 

[2strokenut]

We today I replaced the fuel filter. No start
Replaced TPS sensor from a running exploder. No start.

I decided to run the codes and these are what I came up with:
211- (M) Ignition PIP signal was erratic or missing - Ignition Systems
157- (R,M) Mass Air Flow signal is/was low or grounded - MAF

and a bunch of lean codes etc since I have a bad egr.

???

 

[2strokenut]

Anyone?

 

[iwannabamedic]

sounds like because it will not idle that something in the air intake is losing the air the motor needs to idle, vacuum leak, really check intake out and the hoses.

 

[2strokenut]

You don't think the 211 code is a sign that there may be a problem with something electrical? ICM? PCM?

 

[Tony H]

How does it run with the MAF unplugged?

 

[2strokenut]

How does it run with the MAF unplugged?

It does not run. It only cranks. If you tow it and put it into gear then yes it will turn on and run perfect.

 

[Tony H]

OK, I was looking at a MAF failure.

If you get it running and hold it at 1500 RPM where you say it will stay running, can a friend pop his head under the hood and listen for a massive Vacuum leak? Drivers side , close to Firewall. The Octopus on the intake manifold has a few hoses and capped off inlets. those capped off inlets tear and the tip falls off.

 

[turboexplorer]

My brothers 91' is doing the same thing, almost. He drove to work went to leave then nothing. His seams to have fuel and no spark. Changed the crank sensor and still no go. Next is the EEC relay. Yours if it starts with starting fluid then has spark but no fuel. Wonder why it would have fuel at 1500+ but it under? Check your crank sensor and throw a multi mere on it and check what the other guy said, the voltage. First at bat and alt, if good check the pump voltage and make sure there isn't a draw for some reason.

 

[2strokenut]

My brothers 91' is doing the same thing, almost. He drove to work went to leave then nothing. His seams to have fuel and no spark. Changed the crank sensor and still no go. Next is the EEC relay. Yours if it starts with starting fluid then has spark but no fuel. Wonder why it would have fuel at 1500+ but it under? Check your crank sensor and throw a multi mere on it and check what the other guy said, the voltage. First at bat and alt, if good check the pump voltage and make sure there isn't a draw for some reason.

I think thats what Im gonna do next. Today I swapped in a computer from a running 93 and still it would not start. Rechecked fuel pressure and its good. No vacuum leaks.

Going to have to test the crank position sensor.

 

[turboexplorer]

Post what happens. Ill post about that relay. It will be in tomorrow.

 

[2strokenut]

It'll probably wont be for a few days or so I'm having surgery on both knees tomorrow. Definitely wont be under the truck for a while haha

 

[turboexplorer]

Ouch! Good luck with the surgery. Both knees, that would be rough.

 

[2strokenut]

Thanks it wont be too bad. Both acl's have been torn for almost 8 years. I bought the exploder to build up and keep me busy while I heal up getting ready to race MX in the fall.

What really sucks is that my friends and I buy 91-94 explorers all the time for around 500 bucks to take out to the desert and run them till the body starts the tear and separate from the frame. We run them for months jumping them 4 or 5 feet through the air, flying over big whoops 50 mph, chasing each other through the desert basically trying to kill the things but they take so much abuse its unreal. And whats even more unreal is that we drive them out to the desert and always drive them back. All we do is chain strap the motor, put on some cheap lights from harbor freight and its ready to chase pre-runners. I buy a decent explorer for myself to build up and keep for a long time and the thing just dies for no reason! And I've only had it for a month or so.

Explorers are addicting, that's for sure.