Hello Everybody!!!!-Help my Explorer 97!!!

[eherna]

Let me introduce myself. I am a 51(close to 52) year-old male. And the reason
I'm here is because I have two Ford Explorers, one 97 and the other a 00. So
you can all see I am a reincident on this Explorer thing. Well, going straight to the matter at hand, the 97 Ex started to develop a peculiar behavior. At first, the only symptom it had was a sudden loss of power(and speed) when traveling between 50-60mph. It was not so bothering because all you had to do was to ease on the gas and then resume(sort of a little ''pumping''). But recently the thing got worse. Now It feels like one piston is loosing power, either current or gas-air. The codes came out: P0303 and P0305. So, I decided to change the plugs and wires as there was no other indication except for those two cylinders misfiring. After that ordeal of hours at reaching things with just your fingertips and back-stretching positions, the job was done. During this procedure, I started the engine after each plug/wire change so I would detect anything that changed. After I changed the first one (#5, I think.-It it the middle one on the driver's side), I thought that the problem was over. But never went inside to feel the truck from the drivers seat. All I did was turn it on(from the outside thru the window, not even seated) and give it a little race turning the throttle. So, the surprise was when I finished and seated inside. The ritmic feel of a piston misfiring was still there, exactly the same as before. So, next step was in the same direction. I swapped the ingnition coil from the 00 Ex on to the 97's. No change. I even tried swapping the PCMs (or ECMs) but they were different numbers and the 97 didn't even start. So, here I am, at the beginning, but at least I have tried the MAS, IAT, and TPS (using the ones from the 00 Ex). I NEED HELP. Can it be the control module(PCM/ECM) or the injectors (#5 and #3). I have erased the codes more than once and only those two come back. One of these times the code for #2 came out, but always with #5. The injectors are ~50$ each so I am not too willing on spending 300$ just to see if something changes. I also was considering on buying a gas pressure gauge, which is a lot cheaper and check the pressure at the rail before actually going to attack the injectors. What do you guys think?????

 

[BrooklynBay]

Welcome to this forum! The fuel pressure gauge is a good idea to start, but I suspect that the ignition wires might be faulty. Test the spark coming off of them to a ground connection. There are many good spark gap testing tools on the market if you want invest a few dollars on one of them.

 

[eherna]

Well, the wires were replaced at the same time as the plugs, with no change in behavior (tested each time one was replaced until all six plugas and wires were done) Also, before replacing them, I pulled each one out off the ignition coil with the engine running to see the arc of current and also to see if one of them made no difference when disconnected, but all had a nice arc of current and the difference with one cylinder ''out'' was clearly felt. So everyone is firing, but still if you hear the muffler you can almost feel like one of more are not firing right. That is why I kinda suspect that It could be injector(s) problem, but then again I'm not too willing to change all of them ''just to see'' what happens. I even had the idea of swapping the ones indicated in the codes (#5 and #3) and putting them on some other cylinders to see if the codes change. That will include replacing the manifold gaskets, but it will be a lot cheaper. It is the work involved that worries me, but being at this ordeal has become a challenge and I really would want to know what it is so I can decide if I can do it at home or if I will have to take the patient to the hospital and pray they have mercy on me...!!

Welcome to this forum! The fuel pressure gauge is a good idea to start, but I suspect that the ignition wires might be faulty. Test the spark coming off of them to a ground connection. There are many good spark gap testing tools on the market if you want invest a few dollars on one of them.

 

[BrooklynBay]

Did you do a cylinder compression test?

 

[eherna]

Well, no I haven't done a compression test. Frankly I'm kind of avoiding that because of the pain it was to change the plugs. And I don't know if there was a compression problem, will it show at all speeds? I mean, is there a way to at least suspect that there can be a problem there? Today I was looking at the motor(running at idle), checking carefully all the hoses and stuff and somehow I managed to get my hand on top of the #2 injector electrical connector. Being there, I wiggled it just to make sure it was making a good connection. Suddently, idle was smooth and the engine was running fine. I just stood there, knowing that I had touched something that fixed everything. My pleasure lasted just a moment, because when I pulled my hand out, the symptoms returned in a matter of seconds. Have I moved the upper intake manifold, moved a hose, what?(apart from the connector) It never got back as I tried and wiggled my hand there again. But, it gave me hope. I've already got the manifold gaskets, as I decided to check the injectors and all the rest of the parts under there. I don't know when I will be doing the surgery, but I will post whatever results I get out of it. Thanks a bunch for the replys, at least I know there is somebody out there that's listening and I hope I will be able to resolve this matter and help others that may have it or will develop it

 

[BrooklynBay]

Did you unplug the injector harness plug to examine the connection on the plug? Maybe one connection is bad either on the socket or on the actual injector. Try using a noid light tester.

 

[eherna]

Well hello everybody out there. It was a looong weekend here in Puerto Rico (we have a lot of holidays) and as you may suspect there was little or no work done on the Ex. Anyway, if you followed all this thread, you'll know I'm going to check the injectors(check the resistance on each and also at each connector, to verify the wiring going back to the PCM), o-rings, etc. I will also check all the sensors and valves that are lurking under the intake manifolds.
I have a question: When I took off the upper (plastic)manifold I noticed there were the remains of something that looked like a silicone-formed gasket. On the lower manifold there were the regular rubber gaskets still there. So someone did not trust the rubber gaskets alone and decided to put some silicone on top of the rubber gaskets? There is no evidence on any book or forum that would suggest doing this, but shall I do it also? Remember this is the gasket BETWEEN the upper and lower manifolds (two three-hole rubber gaskets). I would appreciate any suggestions before I reinstall everything back, hopefully this weekend. I will let you all know what happened.....

 

[Rogers-Explorer]

eherna,

I found the same on my '97 XLT - do you have an OHV or OHC?

You can check this thread (http://www.explorerforum.com/forums/showthread.php?t=192154) to see what was up on mine.

I wouldn't suggest putting any RTV/silicone if you are replacing the plenum and fuel rail gaskets. I tried to use silicone on mine when it looked like the gasket on the top of the intake manifold (bottom of fuel rail) wasn't in very good shape. It created a worse vacuum leak and just created a bigger mess to clean up. When I replaced the gaskets after cleaning everything up things seem to have settled down - no more vacuum leak, and no more CEL (knock on wood). And besides, the manual doesn't say anything about adding anything other than the gaskets...

Make sure you torque the studs down properly and as was mentioned earlier, take the time to inspect your injectors and replace any o-rings (or all of them if you want) that look chewed up as well as the fuel pressure regulator. Remember to put a little engine oil on the injector o-rings prior to pressing them back in to their recesses, it will help you along and keep them from getting damaged/pinched. I found it easier to attached the injectors to the fuel rail first and then carefully press each injector into the manifold one at a time starting at the front of the engine and then gently rock the fuel rail back and forth - you can see most of the injectors slipping into the ports easy enough. But, be especially careful around the injector in front of the fuel pressure regulator.

I found it helpful once you torque down the fuel rail and reconnect the electical, fuel ines, etc. to reconnect the battery and turn the key on (without turning the engine over). This will energize your fuel pump and repressurize the fuel system. At this time, walk around and check to see if you have any leaks - it will be very apparent if you do. It saves a lot of time and heartache, especially if your fuel injectors or lines leak after you have replaced the plastic plenum and have everything else hooked back up, which is what happened to me. Fuel came shooting out of the fuel injector in front of the FPR after I had everything back together - very frustrating.

Sorry for the long post but it's a long weekend here and I have the extra time to sit and type. BTW the information I gave was for the OHV - I'm not sure how different it is from the OHC.

Good luck on the job.

Cheers, Roger

 

[eherna]

Ok, so I'm back. As I mentioned earlier, I got down to the injectors, o-rings looked fine and the resistance at each connector was almost the same on all of them(also on the wires going back to the PCM). As I was there, I checked all the hoses and the PCV. All looked normal. So I reassembled everything and started the engine. It started, so I guess I got everything on its place. I did not use silicone on the gaskets, like someone did before on this engine. Well, the misfiring is still there. It is less obvious, since now the gaskets are new(the difference is noticeable) and also the fuel filter was changed, which helped a bit also. One thing bother me, and that was the absence of pressure on the fuel rail when it was dismantled. Everywhere there are warnings and procedures on how to release the pressure prior to open these tubes, but mine had no pressure. There is one procedure that tells you to disconnect the inertia switch and run the engine until it dies, but mine won't even start with this switch disconnected. It looks like the pressure is not being sustained in the system. The question is: will something like this affect only the middle cylinders(2 and 5)?. These are the only ones reported by the OBD, and only as misfiring(codes 302 and 305 ALWAYS-no other codes never). To recap, the truck is a 97 XLT 4WD with a SOHC 6cyl, auto trans. So far, I have changed or tested the following parts: MAF, IAT, TPS, IAC,plugs and wires,upper and lower intake manifold gaskets, injectors and o-rings, fuel filter,ignition coil, PCV. Things left: fuel pressure check and compression test. Anything else I'm missing? Help!!!

 

[Rogers-Explorer]

...One thing bother me, and that was the absence of pressure on the fuel rail when it was dismantled. Everywhere there are warnings and procedures on how to release the pressure prior to open these tubes, but mine had no pressure. There is one procedure that tells you to disconnect the inertia switch and run the engine until it dies, but mine won't even start with this switch disconnected. It looks like the pressure is not being sustained in the system...

eherna, the truck is not suppose to start when you disconnect the inertia switch. The inertia switch is a redundant system that automatically cuts off fuel flow to the engine if you are involved in a collision ... avoids fuel spraying out into the enigine compartment and igniting ... so the fact that it won't start is normal.

Regarding the sustainment of fuel pressure ... my truck is the same way ... if it sits for a relatively long period of time (say 20-30 mins), there is almost no fuel pressure at the fuel rail. I'm unsure of the tolerances with the fuel system and its pressure (how much pressure is lost over a certain period of time), however I haven't had any problems as once the key is turned on the system pressurizes in a very short period of time. I believe the pressure is critical after the key os turned on, not before.

Cheers, Roger

 

[eherna]

Hi, everybody!!
Well here are the latest things that happened. Like I said before, after the last operation(checking the injectors, connectors, valves and sensor cabling under the intake manifolds) the truck had almost the same symptoms as before but the misfire was a little more pronunciated. You can almost hear it at the muffler. So, reading other threads I learned about cleaning the IAC valve and the Seafoam treatment and decided to do those in an effort to make the truck drivable. I mean, you could drive around, but acceleration was bumpy(like running on 5 cylinders) and the idle at the stops was like riding a dragster(shaking from side to side). Still, the engine woudn't stall. The IAC was not particulary dirty but I cleaned it anyway using the electrical parts cleaner. After that, I started the engine to see if anything changed and the idle was a little smoother and higher rpms. Ok, so I went for the Seafoam. Reading around, the trick here is to get the seafoam mixed with the air going into the cylinders. So I took one of the PCV hoses and poured some of the stuff with the engine running. A little shake of the engine was all that happened. I know the guys that gave the instructions do it differently, but I know that the stuff was getting where it was supposed to. But no smoke. Nothing. I did this like three times, let it rest and started the engine again. But no smoke still. I noticed that the idle was less shaky, thought. I then pulled the hose that feeds the IAC from the main intake hose at the front of the car and pured some more. This time it shook it it was going to die. The rest of the can (about 2/3s) went in to the oil and gas. And you know what? It has been 2 days after this procedure and the engine keeps on getting better. It has more power than it had before all this started, accelerates effortlesly and the idle is getting smoother with time. I now think I should have done this before all the rest. I would still have skin in my knucles. I can still fell the misfire, but it is definitively getting smoother. The thing is that I have only used the truck to get to work, which is only a 3-4 mile ride and it looks like it needs more riding. Maybe all of this was caused by a sticking valve or something related to that and the seafoam is doing its trick. If it is in fact a clogged injector, then all of those fluids they sell you at the auto parts for injector cleaning don't work because I think I tried 'em all. This is the first time I pour something in the engine and get results so noticeable or fast. So, I will be moving to the next project, fixing the driver's side power window(motor works, window doesn't move). Thanks everybody for your inputs and support and I'll see ya on other threads!!!!! Keep this site going!!!!

 

[daffy]

I wouldn't leave that in my oil too long if I were you.

Most guys do it a 100 miles before an oil change, otherwise your oil is thin, and most likely your oil filter is clogged from the crud it loosened up.

Great news that your X is running better!

 

[eherna]

Are you refering to the Seafoam? I don't remember reading that on the can, but it is time to change the oil and filter anyways. I was going to add another bottle of Seafoam as part of this oil change(1/3 on the crankcase and 1/3 on the gas tank) since it is feeling better every day but feels like somehow it needs a little more. Now you tell me it is something I shouldn't leave on the oil. Is this right? Please respond or if someone else has an opinion on this I would surely like to read it. I just don't understand how they sell this thing and don't tell you that it has to be removed before certain period of time, if I'am understanding what you wrote. Is it the same for the gas? I mean, how many times can you use this thing(1/3 of a can) on your tank before it does more damage than good?

 

[97greenmonster]

O dont think the gas tank really matters, you just have to worry about the fuel pump sucking up some of the grime from the gas tank and blowing your pump, but the oil, if there was alot of "crud" in the motor, the seafoam does suck a great job of breaking it free from motor components, that it could clog the filter over time. I would recomend using the seafoam, like daffy said 100-200 miles before oil changes, and if it works well, do it after every oil change for a while, and use synthetics, they also break the grime away, but not nearly as good as the seafoam, and the synthetics are a better oil anyway. Glad you fixed your problem. One thing on the OHC, make sure your timing chanin tensioner was replaced, or youll get a beastly rattle over time, and if the tensioner fails, valve and cylinder damage could be done.