94 with rough idle and no power -egr?

[audiodude332001]

So i just picked up a 94 explorer with 80k miles on it. 4.0, auto. The guy that i got it from eliminated the egr by blocking it off on the intake and on the exhaust manifold. When you first start the truck it runs like crap until it warms up, then it smoothes out but has no power at all. also if its cold and you step on the gas when it is in gear it hesitates for a second or two before the truck actually moves. I have replaced the plugs, wires, fuel filter, cleaned the mass, throttle body, tps, and iac motor, but it hasnt helped much. got alittle better throttle response, but not much. i did notice that when the truck is idling like crap, if i unplug the mass it runs better 'sometimes'. some days it runs good with it unpluged, and some days it only runs good with it pluged in. I even tried replacing the mass air flow. im so stumped on this. i dont know if eliminating the egr messed it all up or what the hell the guy that i got it from was thinking. he told me he was a mechanic....yeah ok, i bet. Anyone got any suggestions

 

[Currency]

Does your check engine light come on any at all? Mine has a few codes it's putting out, One is a problem with the MAF and mine also runs like crap when I first start it. I unplugged my MAF and it idles better at start up.

and it with showing 80k miles, You sure its not 180k? I would check the title to see if it's mileage exempt, If so then it should have over 100k.

-Currency

 

[motopsycho650]

The hesitation when you push on the gas is likely the mass airflow sensor. If you take it off and hose it out with carb cleaner, it usually helps.

For the cold starting, try this... Turn the key on and listen for the fuel pump to turn on, then off a few seconds later. Turn the key off, and then back on repeating the fuel pump cycle 3 or 4 times. Then start the vehicle. If the rough running goes away, you have a problem with the fuel lines holding pressure. Likely the check valve on the fuel pump, but could also be the pressure regulator or a leaking injector. I just recently solved the same symptoms on my '94 by replacing the fuel pump.

My educated guess is, since '91 & '92 explorers did not have EGR's, having the EGR disabled shouldn't effect running that much. It would likely fail Colorado's emissions requirements, but I would think it would still run. The EGR system should be throwing a check engine light if it's been plugged off.

P.S. to Currency, my '94 has a 7 digit mileage display, therefore it won't "roll over" until 1 million miles. The '94 I bought had only 108k, owned by an elderly couple, kept in the garage, never been off-road. 200 bucks with a bad transmission, not too bad...

 

[Currency]

I would recommend mass airflow cleaner. Many users here will tell you not to use carb cleaner on your mass airflow.

http://www.explorerforum.com/forums/showthread.php?t=156916&highlight=clean+maf

BTW, I've never seen a 91-94 explorer with a seven digit odometer before

 

[rileyrs]

carb cleaner works fine on the first gen mas.
did you try what motopsycho650 said to do with the fuel pump.
is there a vac leak, cuz that would also cause alot of the problems your describin.
is it throwin any codes?

 

[Joe Dirt]

Why would carb cleaner work fine on the gen I MAF, but be non-MAF friendly on the others? Only asking so as to have good information here for everyone...

 

[audiodude332001]

Yes the truck only has 80k original miles. It is a 7 digit odometer. I changed the mass air flow and its runnin a lot better and not hesitating. Still not much power though. Also the check engine light is on, but the codes only come up as egr

 

[rileyrs]

the first gen maf has a thicker stronger filament that is only one piece and is easy and safe to remove, the other seem much easier to damage, and are much more sensitive, therefore you should use a specially formulated maf cleaner.

 

[audiodude332001]

So the truck "runs" good now, but now the motor is ticking when under load. Up hills, stomping on it, etc. I know this is common, but what is the fix for the ticking? My last explorer that started ticking got a 302 to fix the problem, but I'm not going that route this time. I'm assuming its the lifters on the top end.

 

[IBW0TRR]

So the truck "runs" good now, but now the motor is ticking when under load. Up hills, stomping on it, etc. I know this is common, but what is the fix for the ticking? My last explorer that started ticking got a 302 to fix the problem, but I'm not going that route this time. I'm assuming its the lifters on the top end.

Possibly the knock sensor assuming your vehicle was equipped.

 

[92exp4x4]

The ticking noise is probably pinging. Your 94 came with EGR and even with it being "disabled" its still trying the calculate fuel delivery and timing as if the system was there and operating properly.

If you really want it to run properly with out EGR, you will have to get a PCM from a 91,92 or a 93 without california emmisions. All 94s had Cali emmisions. Only problem is the 91,92s have a different PCM harness so your are left with finding a non calif 93 PCM or rewiring the harness to accept a 91,92.

If i were you I would find all the EGR parts and stick them back on the truck. After all it was designed to have it there. Check your lower intake bolts for proper torque and fix any codes the truck is throwing at you. Do a tune up and a new air filter. This should take care of your performance problems. Try also searching the threads for pinging or pre-ignition fixes to get info on the problem.

 

[huntman58]

Yes the truck only has 80k original miles. It is a 7 digit odometer.

I have a 93 and it also has 7digits but one is for tenths of a mile and the other 6 are for miles .That is the only kind I have ever seen be it sales lots when they were new or now in junk yards .

Soooo if it is a real true 7 digit deal would love to see a picture of it being I have never seen one on a 1st gen ex!

 

[92exp4x4]

I have heard of it one some later production 94s and foreign trucks. All mine have the 6 digit.