hello i am new here. i have a 93 explorer with the 4.0L . i recently bought it and took the engine out because of a suspected broken crank. it ended up being the aluminum spacer on the back of the crank. but anyway i am not sure how it ran before i removed the engine but now the power surges pretty noticeably and the check engine light comes on. the codes it gives me are for the HEGO system always rich or no HEGO switching detected, EGR valve opening not detected ( which mine doesnt have an egr on it. i was told that on some fleet models it was not put on), and SPOUT circuit open or grounded, spark angle word failure or ida circuit failure. can anyone help me out here as i have done everything i know to do with out bringing it to the dealer. i have recently replaced the o2 sensors which i think is the HEGO part. this rig is in excelent shape except for the surging so i would like to get this figured out. thanks for all the help.

 

anyone have any insight?

 

Yes sorry - the holiday weekend will take us a bit to respond.

I've yet to rebuild my 4.0 so I am not familiar with the aluminum spacer on the crank that you reference. I can help you with the codes and possible inferrences. Yes HEGO means Heated Exhaust Gas Oxygen sensor. So changing both of them is a good start - you did change the right and let ones right?

I need the code numbers so I can tell exactly what your PCM is telling you. Please provide. But from what you describe, you have some ignition problems. Maybe it's a bad ICM - Ignition Control Module. This is located directly in front of your battery.

The EGR code is defintely bissare. If you don't have an EGR system, the PCM shouldn't be looking for a signal. I think every state, CA + Fed, required a EGR in 1993. So if you don't have one, someone took it off. Does your truck have after market headers on it? If it never came with any EGR, the only way to get a EGR code is if someone change the PCM, Powertrain Control Module - or the car's computer - with a PCM from a car with a EGR. If this happened, you could have variances in the cable pin outs that may be contributing to your problems.

Let me know your PCM part number and the code on it. Remove the right side kick panel and read the numbers of the unit there. Should be something like F37F-12A650-YB or something close plu the code of BAT1of some other 4-5 digit alpha numeric code. I have somerefernec material that might help us figure out if you have the wrong computer - oh yeah, let me know aht vehicle you have. Manul/Auto trans? what state is it from? Is it 4WD? Any other modifacations you know of like cold air intake, MAF sensor change, different injectors...

 

the explorer is a 1993 xlt 4.0 automatic 4x4. the ac compressor and hardware has been taken off and the hubs switched to manual instead of automatic locking. it had some head work done to it before i got it not sure what the garage did to it though. as for the codes the first time i ran the code reader it came up with 18,173,61,63. i have also replaced the tp sensor. then about a month later i ran the codes again after changing the o2 sensors and came up with 33,18,31,75. and now to run out and see about the pcm number
eec lv efi ma46g
f37f-12a650-aab
63emg6a16 47303-66 3a25
not sure which one it was that you needed so there they all are. thanks

 

Wierd. Let's make sure you have a solid baseline. Now that you've changed some parts, HEGO's, you should disconnect the battery to clear the KAM and all computer learned correction factors. Not sure if you did this yet. Then run you KOEO/KOER tests then check for codes. Not clear from your post if you ran both tests or just KOEO to get the codes.

So if you did all this and now are getting 18,31, 33 and 75 that's OK - this is the new baseline.

Your PCM is not on my list from a TSB that changed the PCM's - Ford updated the start-up and engine cold tables to prevent stalling. I don't see any 49 state (fed) automatic trans cars on the list so no big deal. It was just a referrence point. But I'm still wondering if your PCM is the right one. If you don't have a EGR, if the car never came with one, the PCM shouldn't be throwing any EGR codes. My car is from CA so it has all the great smog devices. But I do have a PCM pinout for federal cars and I don't see any reference to EGR inputs. Maybe the garage changed the PCM thinking it had a bad computer - which is dumb if they did. Computers don't go bad. Even the power to the computer is protected by diodes so you can't hook it up backwards and fry it. But the F37f-12A650-AAB is a 1993 Explore PCM - at least the one I saw on eBay with this same number said it was a 1993 Explorer. Ford dealers may vary on their ability to do this but check one to find out what PCM they list for your car. Finally, if a EGR was installed and now removed, you'll need a custom chip for your PCM to deprogram he EGR function out of the PCM. This is theoretically possible but you may not find someone willing to invest the programming time for your PCM (i.e. SCT, Diablo...)

Code 18 SPOUT circuit open. This shouldn't be a big deal but does affect spark timing. The car can run without SPOUT but at a fixed 10 degree BTDC spark advance. So it will not have a lot of power but should still rev up smoothly. There is a jumper in the wiring harness that might have been removed. Maybe the shop did this thinking they were removing the octane jumper - you remove the octane jumber to check base timing which should be 10 degrees BTDC. Anyway, the SPOUT jumper is located next to the ICM - ignition control module which happens to be right in front of your battery. Need to remove the battery to get at it - which is OK if you need to clear your KAM anyway.

Codes 61 and 63 for engine coolant temp and TPS both too low in value - not worried about those. Car was not up to temp when the test was run. And 75 says your brake switch was on the entire test time. Did you have your foot on the brake?

Now for the surging, a vacuum leak can cause this type of response. You can check for that. The tree on the back of the manifold has some hard to see ports and you can loose a plug and not know it - happened to me once.

A few things for you. Let us know what you come up with.

 

Double check that all wiring harness connectors got re-connected after engine R&R. I had engine rebuilt in my 91 and shop left 1 connector disconnected. On mine, there were 2 main engine connector assemblies around the alternator. The smaller of the 2 (and slightly hidden below the alternator) was left unconnected. I noticed it as loss of temp gague reading, but it had 4-5 wires in it so not sure what else was affected as I did not drive it away from the shop till it was fixed.

My 91 also does not have EGR or cam sensor. If yours is throwing these codes only 2 possibilities exist. Someone swapped in an earlier engine or modified the original engine to remove these items, or swapped the PCM to a later version that "thinks" the engine is so equipped.

Clear all memory and re-run ONLY the Key on Engine off self test. Your codes do not make sense as you gave both 2 digit and 3 digit codes. You cannot have both types.
We can then go from there to help you.

Dialtone

 

Why can't you get 2 and 3 digit codes? My 93 does. Unfortunatley though since when it does I have to go and fix.

 

Per Haynes manual, 2 digit codes range from 11 to 98. 3 digit codes range from 111 to 998.
If someone posts a code 2 digit code of 18 the equivalent 3 digit code is 213. It just does not crossrefrence directly by adding an additional digit to a 2 digit code to get a 3 digit code (except for 11 and 111 all tests pass). Can only be 2 or 3 digit as far as I can see.

By the way F37F-aab shows to be a correct PCM application for a 93 explorer 4WD per the autozone web site (but it also lists 6-7 other different possibilities)

Dialtone

 

So I am a big fat, well not really fat, liar. I checked my notes when I got home tonight and I have never gotten a 2 digit code. I did see the description duplications in the 2 digits and 3 digit lists. Like system pass 11 or 111. So I'm inclined to think Ford ran out of available codes 99 or 88 available with just 2 digits was enough so they went to 3.

So the 173 code here was for a O2 sensor - it got changed and the code went away. I wonder if it was ever present or a possible misread. Was the CEL pulse method used or an actual scanner/meter. If the latter, maybe it's defective or the wrong engine code or vehicle year was entered?

PCM's - seems there were defintely a lot, especially after the TSB went out. Mine is a CA, 93, manual trans. It did get upgrade/changed out to a F47F-12A650-CTA. Ford dealer only lists this new number and the old number is superseeded in the system to the new one.

FOOF187 says he rebuilt the engine so unless someone else put in a different one, it's original to the car. If the EGR is/never was on it, then someone changed out the PCM.

Wait for his/her response at this point I guess.....

 

the pcm is the same one that was in it when i bought the explorer. however i dont know what was done to it before i got it. i have some various receipts from the previous owner but all that is for is shock replacement and some head work. it doesnt even say what was done to the heads. i have never dealt personally with this garage but from working at a napa store where we sold them all their parts my gut feeling is telling me that swaping in the wrong pcm could be a possibility. as for the code reader it was an el cheapo one that you can get for like 30 bucks where it just flashes the light and you count how many flashes it gives you. the last time i used it i got fed up with it because it was getting really hard to tell was was a break in the code sequence and what was a pause for the second number and so on. after replacing the hego parts i disconnected the battery, actually had it disconnected while i was doing it just in case of and shorts just wanted to be on the safe side so the codes should have all been cleared. as for the SPOUT this is also something i will look into to see if maybe they disconnected it and didnt hook it back up, again not too confident in the garage. could this connection possibly have a short in it? the engine revs like normal but feels like it is running on 4 cylinders and then if you are excellerating with your foot in a steady place the rpm's will jump about 500 rpm and it will feel like the other 2 cylinders have all of a sudden kicked in. feels kind of like the timing is off then all of a sudden changes to where it should be. for the brake signal reading i did not have the break on. really hard to do with the tester i have because you have to be right at it to see the blinks of the light and the test connecter is by the passenger firewall. i am pretty sure that all the vacuum hoses were hooked back up( how many times have you heard that) but i will check those again and see what that gets me. what is the TSB that you are talking about i am not familiar with that? i probably wont have time to check this stuff till the weekend so i wont have any new info till then. thanks for all your help and digging around that you guys are doing for me. hopefully i can get this thing staightened away.

 

oh one more thing i dont think i have mentioned, i am getting around 10 mpg and i know this isnt right. i am guessing that part of it is that i have my foot in it more because the power is lagging.

 

SPOUT circuit might have a short. It does sound like the SPOUT could be causing your poor performance. If you don't get spark advance you don' get a fast rev. Look for the SPOUT jumper. Mine is gray I think. It's a little plastic plug with a metal strip that jumps the 2 wires when placed into the connector. Again, it's right in front of the battery coming off the ignition control module. You'll know it when you see it.

10 MPG is realy bad. I wonder if you are running rich too? Any black smoke out the back - even a little?

With the blinking light testor, and the problems you had with it, I'm questioning all the codes you came up with. I've neve used one or tried to do the CEL blinking test (where you could put a foot on the brake) because it looked to complicated for my simple mind. I use azn Autoxray unit that has been great. You can find it on the web for ~$130. It tells you the code and description with some explanation of what could be wrong - all in English. If you get a better code reader, or go by Autozone for a read, it might tell you what's been going on now since you've disconnected the battery.

 

well i just went and looked at some stuff. the SPOUT connector is in place. all the vacuum lines have hoses or caps on them.i took the SPOUT connector off to see what it would run like without it and it had a little less power than what i have right now so that leads me to believe that it is doing some good. by the way does anyone know what SPOUT stands for cause it doesnt have that in my repair manual. if i get some more time today i will try to run it down to m&o and use their tester and see what that gets me.

 

Some additional info on the subject SPOUT / SAW:

http://www.dainst.com/info/edis/edis.html
Without an ECU the EDIS system will fire the ignition at 10 degrees BTDC (Before Top Dead Center). The spark advance is controlled by the SAWPW line on the EDIS module. The SAW (Spark Angle Word) is analguous to the SPOUT (Spark OUT) line on Ford TFI-IV systems. The interface is different though

Dialtone

 

SPOUT = Spark out. The ICM sends PIP (profile ignition pickup) to the computer, PCM. This is basically #1 cylinder TDC and RPM. Then the PCM says, OK thanks, now I'll look at engine load, TPS, EGR and other factors and sends a SPOUT back to the ICM. This SPOUT is the conditioned spark signal that is advanced or retarded depending on what the PCM figured out. The ICM then fires the coils. Seems like a lot of thinking but the PCM is powered by an Intel chip so it goes pretty fast. Since I work at Intel, I guess I'm biased.

OK so SPOUT is hooked up but is there an intermittent short giving you the code. Check too if the octane jumper is installed. This is the same looking jumper but located next to your DTC ports. It would only pull out 4 degrees of advance if not connected but could be adding to the problem.