94x dies after driving for like 20 minutes

[X94]

when it's cold outside, i can drive fine. but when it's hot outside i can barely get a few miles down the road to work. it dies and then it won't start for like 2 to 5 to 15 minutes. then it runs rough and not for long before dying again. if i have to sit for longer than 20 seconds at a stop light, there's trouble. if i leave my explorer parked in the sun after driving a few miles, it might not start for a while when i get out of the store.

i've been driving with the heater on to help reduce the heat because the problem is worse when it's hot out and and when the engine is hot.

i tried replacing the water pump and thermostat, i've done several cooling flushes and have plenty of coolant. i replaced the spark plugs and must have overtightened one because it ran like crap after, until one night i could see the spark plug flashing and replaced it. that cured the terrible idle but before i found that plug, i took my explorer to a ford specialist for a diagnostic. they said my codes said something about my o2 sensors and they did a heat reading in front and back of my cat and determined my cat wasn't letting enough heat through so it was probably bad.

then one day my muffler blew off the back of my cat ( i have a lot of underbody rust ) so now i have it tethered there with a wire. the ford specialist quoted me $1000 to replace the cat and o2 sensors. the parts at autozone would be about $300 total so i can do that part myself. but then i need to get a new muffler too and have it welded somewhere i believe.

so here's my problem, i can't afford to replace my entire exhaust system yet and it's starting to get hotter outside. is there anything physically possible that i can do temporarily to keep my car from dying in the heat? i've tried drilling a few holes into the beginning of my cat because i didn't want any other part of my exhaust to explode. if i take my cat completely off, will that keep my car from dying in the heat?

 

[runningred92]

Its not legal to take the cat off but I have seen where some people on here have talked about gutting their cats and leaving it in place. Not sure exactly how one would go about gutting it but im sure if you look around here you will find something about how to or at least see who said they did it and send them a private message on how to go about it.

 

[Anime]

Might be the ECU. Mine was the opposite, it wouldn't start when it was cold out, but started fine in warmer temps. The capacitors leak and cause electrical issues. Usually not starting is a symptom, but also the codes usually can't be read, though it depends which caps go bad.

It's best to use the suggested OEM Motorcraft plugs, you can get some pretty terrible results with certain aftermarket brands.

As for the exhaust, the easiest thing might be to get a Dynomax cat-back kit. They're only like $150 and include the front pipe, muffler, rear pipe, clamps, everything. You can also get Thrush mufflers for $20-30 at Advance Auto Parts, and just use them with the 2"/2.25" Walker/Dynomax pipes that you can buy seperately for a 93/94 Explorer.

The catalytic converter is ~$188-200 for the stock 2-converter pipe, but you can also get a single 3-way converter for like $40-80, have it welded to an ovalized pipe in front, a round pipe in back to match the stock pipe size, with a flange. Stick the gasket on that, attach the cat-back, all new exhaust.

O2 sensors can go bad if they are fouled up from a fuel/air mix that's too rich, so if you had fuel/ignition issues, either from the spark plugs not burning all the fuel, or the ECU just being screwy, you should definitely replace whatever is causing the problems first, then the sensors.

 

[X94]

ok i solved the problem.
i replaced my O2 sensors and that did nothing to fix the heat problem. i wasn't able to get the 3 bolts off my cat to separate it from my Y pipe but a friend of a friend was able to and he also bolted up a new one and attached it to my muffler with a donut and collar, all for $80 labor. that didn't fix the heat problem so i replaced my EGR valve, and again, no success. my fuel filter sounded quiet to me so i replaced it and had to buy a fuel line repair kit because i broke the fuel line teeth. the x ran like a champ for about a week then it started sputtering and dying again. replaced the fuel filter, dark gas was falling out of it, i thought it was a good sign... still sputtered and died after warming up.

today i googled it some more and found this
http://forums.corral.net/forums/94-95-tech/1354945-95-5-0-loosing-fuel-pressure-2.html
where someone had a similar problem and replaced almost everything on the car like i did. im pretty sure the problem from the start, over a year ago now, was the fuel pressure regulator. i put a new one in it and so far it's steady as she goes. i spent a ton replacing worn out parts that weren't the problem, but at least i have a lot of new parts and it's a well oiled machine now.

so for anyone trying to solve their problem with a google search, here are the symptoms i tried googling---> if your car runs fine for 10-20 minutes but then struggles and dies, it could be the fuel pressure regulator. if it won't start back up after you drove it for a while and left it parked for a minute, it could be the FPR. if it starts back up for you after sitting and you go to drive it but it stalls or dies when you hit the accelerator, it could be your FPR. if your car seems to drive fine for a while but then chokes and dies while waiting at stoplights when it's hot outside, could be FPR. if your car seems to overheat and stall even though the temp gauge doesn't show it being too hot, could be the FPR.

 

[X94]

scratch that. car drove perfect for a week then started doing the same thing. im so sick of this problem. everything i try as a fix, makes it all better for a week or two like a placebo and then it starts dying every day again
looks like there's another thread with lots of people having my same problem.
http://www.explorerforum.com/forums/showthread.php?t=350037
i've replaced everything but the kitchen sink. i don't understand what else it could be!

 

[tweakedlogic]

For over a year I had a crappy running Rx7. I did everything I could think of. Finally, I came to a few sensors i hadn't yet replaced. As soon as I replaced the air intake temp sensor, the car ran perfectly.

Have you pulled the codes? It very well might be a computer issue, but not in the way you think. It seems to me that when you change a worn out part, the ECU sees this change and is learning how to adjust it's maps for what it thinks is right. Unfortunately OBD1 won't let you see what the sensor sees.
Pull the codes and right them down, date and time stamp the record. then clear the codes before you change a part. Drive it, and pull the codes again, date and time stamp, clear the codes again. Keep a journal of everything you do, how many miles you drove before it messed up again the codes it had when it quit. Include details of the day/miles/temps (engine and ambient), everything you can think to document, put it in the journal. It may help you diagnose the problem. Keep the journal in the car of course.

Start with testing the temp sensors, air and coolant, don't overlook your throttle sensor. Test them to make sure they are falling in the right range. Don't just throw parts at it. Test them. If you are in doubt about the results of the test, you can then replace it.

The coolant temp sensor is easy to test. Remove it and take it inside. it is supposed to have a certain resistance for a given temp. Easy enough, What's the first thing they do in the movies when someone goes into labor not in a hospital? Boil water. Use cold water with the burner on medium and an instant read thermometer (calibrated), your sensor hooked to a multimeter. Then watch and verify the numbers are correct using the thermometer. I don't have the resistance numbers in front of me. maybe someone can beat me in finding it.

Optionally, most sensors are pretty cheap, if you want to just replace them and save yourself the trouble, it can't hurt.

 

[X94]

i got a loaner fuel pressure test kit from autozone for $150 and tested the fuel pressure at the rail, it was like 30 when the x first started. then after running for a while and warming up, the pressure dropped down to like 20 and the engine started sputtering a little and it went down to like 8 psi and so on until the engine choked itself out. then i tested the pressure coming right out of the pump and it was only 10 psi. i tested the plug with a multimeter and it said 12v.

i've been reading that lots of other people have been having trouble with airtex pumps. one person on a thread that worked at an auto parts store said they had a 20% return rate for airtex pumps in the store computer system. autozone only has airtex pumps and an installed pump can only be returned for store credit or an exchange. i didn't want to keep going through airtex pumps so i just went to advance and special ordered a delphi fuel pump for $130 and an ac delco fuel filter for $25. i just finished installing it a few hours ago and the psi is a steady 30 and i haven't been able to get it to stall again.

now i can take back this fuel pressure kit for the 150. tip for everyone dont buy airtex fuel pumps and make sure you buy a new fuel filter if you replace your pump

 

[Dano!]

That's great that you were able to identify your issues and fix them. The only thing i got fought up on is when you mentioned there was black fuel comming out of the fuel filter. When you had your tank out did you clean it out?

If you have problems in the future it might be debris somewhere. Dirty tank, or anywhere in your fuel lines can gunk up at any number of places and cause issues. I hope all is well though. Good job. And good luck.

-Dano

 

[X94]

2 weeks later and still running strong. im shopping at advance auto from now on

 

[X94]

ok.... car started acting up again last week. borrowed a fuel pressure test kit from autozone and i only had 15 psi at the fuel rail. so i disconnected the fuel filter and blew air up towards the engine with the fuel rail fitting held open. then i wanted to siphon the gas out of the tank by taking off the filler tube. when i started moving the filler tube this time, it sounded gravely so i started yanking on it and realized it the steel filler neck was rusted under the hose!!! SO EVERY TIME I WAS PUTTING GAS IN MY CAR, I WAS PUTTING MORE RUST IN MY GAS!!!! *punches self*

i went to the junk yard and got a new filler neck and tube and everything for $8. rinsed and dried the tank, put a new fuel filter, put a new fuel pump after taking the other back with the warranty, and now im sittin pretty.

yesterday i replaced the dpfe, iac, and iat so now my idle is steady and the acceleration is smooth. IM SO HAPPY! it's going well over 4000 rpm which is good because it was just bouncing at like 3500 - 3700 - 4000 when reving in park. i was reading other threads about the problem possibly being the camshaft position sensor. i was not looking forward to replacing the cps because the synchronizing sounds difficult. and now i dont have to because the fuel pressure was the rpm problem

i take back all the bad things i said about AIRTEX fuel pumps