So my 1995 explorer (4.0) is acting like it has a miss. This started after I removed the muffler because it had rotted out. It was sporadic and would clear up but is now constant. It idles okay but rough and drives okay just low on power. I don't have a check engine light but it will pop-up once in awhile and always has.

I checked the spark plugs and wires (replaced about a year ago) and they look good and pulling off the wires one at a time from the ignition coil pack there is little change. The plugs looked good with none showing unburned gas or black/sooty. I checked the egr with a vacuum pump and it bogged the motor badly. Engine vacuum sits at 18 at idle but drops immediately to zero when the throttle is cranked. I don't hear any hissing and checking vacuum lines with the pump and a gauge I don't show any leaks. I've also sprayed throttle cleaner around the hoses and egr intake hose with no noticeable throttle difference. I'm not sure how to check the crankshaft position sensor but I have no issues starting it.

It feels like timing off or a vacuum leak but I can't find an issue with either and not sure how to check the timing (no clue where my timing light is) I think I found the timing plug doodad(technical name) behind the ignition coil. Thought about unpluging it and seeing if any change. Would the muffler being missing mess with the o2 sensor and cause it to run lean(doesn't seem to be rich but smells as if it could be running lean)? Not sure what I'm missing but didn't know if anyone here knows of something to check that I'm overlooking.

 

And now I have water dripping in the back. Looks like the drivers side head freeze plug possibly has a pin hole.

Pulled some codes today. 335, 332. Running 326, 536, 632. The one code is because I didn't cycle the o/d button and the other because I didn't do the brake pedal? Looks like egr but it tests good. Gonna look at the PFE next and maybe the crankshaft Position Sensor.

 

Have you checked the joint and rigid metal tube that connects the EGR to the exhaust? Since codes point to EGR, this started after doing exhaust work, and an issue with the EGR tube could cause a vacuum leak, it seems like something worth carefully inspecting.

-Rod

 

I sprayed carb cleaner around the tube and fitting going into the intake. Didn't seem to change the idle speed. I sprayed all around the intake and hoses to see if I could find something but no luck.

 

But doesn't the EGR tube on the 1995 Explorer have a hard fitting at one of the exhaust manifolds? Did you check there? I don't really recommend spraying carb cleaner on a hot exhaust manifold so start with a visual inspection or spray immediately after start up on a cold engine.

-Rod

 

It does with two ports coming up to the sensor that helps control the EGR I believe. There is no exhaust leak there that I can tell and should be very noticable if there was. And yeah I didn't want to spray carb cleaner onto the hot exhaust. I did check the rubber hoses coming up for leaks and found none . I thought about replacing them but was wondering if they were special since the exhaust gases would be pretty dang hot. I had a couple of vacuum lines bad right around there when I first bought the vehicle.

 

I'm getting no vacuum from the hose going to the egr at idle which I suppose is correct. If I pull the hose there is no change in the idle quality or rev quality. Still low on power. So I'm wondering if I have an EGR valve that is stuck partially open. Can I remove it and plug the hole going to the intake and see if that is the cause? It will try to stall the engine if I pull a vacuum on the hose going to the egr with a hand vacuum pump. I'm also getting an egr cel code on the regular now even after clearing codes but I don't see how the egr valve itself would kick a code since it is a mechanical mechanism. If the PFE was bad I'd think it would change the idle when I pulled the vacuum hose from the egr. Really scratching my head with this. The car runs fine but a lose of power and feels like a miss. Doesn't stall out or not start.

 

At idle there should not be any vacuum to the EGR. If the EGR opens at idle it will be a vacuum leak and the engine will stumble and/or stall. It sounds like you proved that too by applying vacuum to the EGR. And the DPFE is not sensing vacuum on that line to the EGR valve, so attempting to pull a vacuum on the line to the EGR valve should have no effect, unless you pull so much vacuum that you internally damage the DPFE.

-Rod

 

I pulled vacuum at the hose heading to the EGR. I tried to get the nut loose from the pipe at the egr today with no luck. I'd hate to break or cut this loose but I may just take it out as a whole unit from exhaust to intake. Then plug the holes and see if it runs smooth. A transmission issue popped up today while going to get gas. C4 is looking like a better fix every day With the frame and body rust I really think it isn't worth the effort. Considering the suspension work I've done, I really hate to just abandon it (new control arms, shocks, hubs).

 

Well, sometimes it's best to cut your losses and move on if you're financially able to do so. There's comes a time when a vehicle wears out and it will just continue to nickel and dime you, or worse. You could fix this EGR issue and have it throw a piston rod through the block. Of course you could also buy a low mileage 2010 (insert favorite used vehicle model here) and have the transmission go out just after purchase too.

-Rod

 

Yeah I've run across a '99 Expedition for 900.00 with a water leak that I'm hoping is just a heater hose. And for 900.00 and no rust (some surface underneath) its miles ahead of the explorer. Really loved the explorer and how easy it is to park and drive. I'll probably keep an eye out for another one down the road to kick it around in.

 

If that Expedition has the 5.4L V8 you will want to find out when the last time the spark plugs were changed and see proof of it if they claim it was recently. The stock plugs have a known issue with spark plugs coming apart in the head. The cost to repair such an ordeal could about double the investment, but with a $900 ask you probably wouldn't have much luck getting the purchase price down if the plugs haven't been changed recently.

-Rod