What are the chances my MIL is burnt out?

[Greg Corcoran]

Just bought another Gen 2 after a 11 years a no SHO here... The car is low miles (77K) '95 MTX overall good shape and garaged, no mods that I can see so far, but has a pronounced stumble when cold from about 3000 - 3500 rpm. Goes away within minutes of startup. (Also needs a CCRM because the low speed cooling fan won't ever come on, but when I jump pins 3 & 4 to 1 &2 the fan comes on. When I ground pin 14, nothing. Former owner knew, and already had another CCRM stashed in the trunk, but he got a "J" and I need a "D" code apparently. NAPA says they can get one by the weekend for ~$125 so I ordered it.)
So- I decided to start troubleshooting stumble by pulling codes.
The method I used on my '92 to pull stored codes all those years ago doesn't genereate a MIL/check engine light at all. I have a short jumper I place between the gray connector and the top right connector on the black EEC IV plug when holding the black plug with the 2 conncection positions "up", 3 positions down.
I also just noticed the check engine light does not come on briefly when I start the car, or if I intentionally stall the car. I thought it did come on as part of the start sequence on my old SHO, or if the car stalled...
Any insight? And if MIL is disabled or burnt out, how hard is it to repair? I apparentkly gave away or sold my Helms manual for the '92, so I can't look it up.

Greg Corcoran
Longmont, CO
(Former member of CSHOC)

 

[Irish Pride]

It could be burnt or it could be covered. The very first SHO I ever bought had a piece of electrical tape inside the cluster covering the CEL. It is suppose to light up on start up with all the other dash lights and then go out. If you don't see it light at all then something is not right. You will need to pull the cluster to get a better look.

Chad Corcoran
Nashville, TN

 

[Greg Corcoran]

Thanks cuz! I was afraid that was the answer.... Now I gotta remember how to pull the cluster. It's been a longggggg time, and my HELMS manual is AWOL.

Greg

 

[Devin]

Here you go!

http://www.shopowered.com/repair/repair-ignition-switch.htm

edit: I just re-read your post and realized you have a gen 2 so the guide won't help.

 

[rubydist]

while you have it out, replace all of the bulbs that illuminate the cluster at night, because if you don't several of them will fail as soon as you put it back together...

 

[luigisho]

There are also cheap OBDI code readers that basically just have a flashing LED bulb to count the flashes and reference the code just like the cluster light.

 

[ISHOU]

Just bought another Gen 2 after a 11 years a no SHO here... The car is low miles (77K) '95 MTX overall good shape and garaged, no mods that I can see so far, but has a pronounced stumble when cold from about 3000 - 3500 rpm. Goes away within minutes of startup. (Also needs a CCRM because the low speed cooling fan won't ever come on, but when I jump pins 3 & 4 to 1 &2 the fan comes on. When I ground pin 14, nothing. Former owner knew, and already had another CCRM stashed in the trunk, but he got a "J" and I need a "D" code apparently. NAPA says they can get one by the weekend for ~$125 so I ordered it.)
So- I decided to start troubleshooting stumble by pulling codes.
The method I used on my '92 to pull stored codes all those years ago doesn't genereate a MIL/check engine light at all. I have a short jumper I place between the gray connector and the top right connector on the black EEC IV plug when holding the black plug with the 2 conncection positions "up", 3 positions down.
I also just noticed the check engine light does not come on briefly when I start the car, or if I intentionally stall the car. I thought it did come on as part of the start sequence on my old SHO, or if the car stalled...
Any insight? And if MIL is disabled or burnt out, how hard is it to repair? I apparentkly gave away or sold my Helms manual for the '92, so I can't look it up.

Greg Corcoran
Longmont, CO
(Former member of CSHOC)

Welcome back to the SHO world. Did you find your SHO in Colorado and may I ask how much you paid? Sounds like a great find. BTW, I grew up in Loveland and now live in Centennial. I rarely see any Gen1/2 SHOs anymore in the Denver area.

 

[Greg Corcoran]

Welcome back to the SHO world. Did you find your SHO in Colorado and may I ask how much you paid? Sounds like a great find. BTW, I grew up in Loveland and now live in Centennial. I rarely see any Gen1/2 SHOs anymore in the Denver area.

No - not a local car - had to fly out to Indiana to pick it up and drive home. Originally a CA car. I'm going to call the price of the car itself $2400, I paid more overall, but got 2 extra left wheels, seats, new AC compressor, and a pile of other parts too.

There are nearly no Gen 1 & 2 SHOs around here any more either, and the ones I do see are beat to death.

Greg

 

[Greg Corcoran]

Here you go!

http://www.shopowered.com/repair/repair-ignition-switch.htm

edit: I just re-read your post and realized you have a gen 2 so the guide won't help.

Devin,
No problem. MIL Light came to life today!! I replaced the CCRM today with a new unit from NAPA because the low speed fan wouldn't come on, and it traced back to a bad CCRM output. The fan immediately ran for a few seconds when I reconnected the battery cable, then shut off. Good sign, just what it should do! Then I went to start the car, check engine light came on with all the others(!!!), the car started normally, MIL light went out, ran properly for maybe a second then slowly petered out to a stall. The check engine light came back on!! Tried to restart and it cranked forever, and check engine light was on the whole time... No fuel I presume.

Clearly this NAPA module is incorrect, mainly because their computer catalog claims it is for all 3.0L DOHC Taurus 92-95, but the forum here states D code is 94/95 MTX only. I tried to explain that to the guy at the counter, but he claimed it was the right module because the computer said so. Next I got ahold of one of the honchos at the store I've known forever and he quoted a different NAPA part number that comes up as 94/95 3.0L DOHC, so we'll try that next. It's on order from Echlin warehouse in Tulsa or someplace.

BUT my main question is how does the CCRM cause the MIL to work/not work? And are the CCRMs repairable?

Greg

 

[Devin]

You can probably find a known good one from someone on here via Want to Buy.

 

[rubydist]

BTW, just for every one's knowledge, you can pull codes even if the check engine light bulb is burned out - rather than putting a regular jumper across the two placed under the hood, you connect a 12V light there, and it will flash out the codes just like the cel does.

 

[Greg Corcoran]

Here's an update to the CCRM and the 3000- 3500 rpm stumble if anyone is interested, and/or has any insight, or even witty banter...
None of the three different CCRMs I eventually got from NAPA worked. Found an NOS D code CCRM using a parts locator service, and it was cheaper than sending my module to an outfit in FL for a rebuild. High and low speed fan, fuel pump, A/C clutch etc all worked. For about 2 weeks. Then the low speed fan stopped working again. Fried the new CCRM!! Turns out there was very little resistance across the windings of the low speed fan, less than the high speed fan even. Not quite a dead short, but heading that way. Grrrr. Although many of the links in older posts about wiring/CCRM are broken, there was one for the PCB 40A relays that was still good so I ordered a few tonight. I really would like a schematic for the D code module though. There once was one here on Shoforum, but it must be on one of the busted links, because I can't find it again.
As for the 3000 - 3500 rpm violent surging/lurching when cold - still there. The code I get is 111, i.e. all is well... So I'm looking for mechanical something? Since the original post I have changes plugs, wires, 60K shim adjustment, plug well seals, etc. (still haven't done the timing belt). The plug wells were FULL of oil. I was hoping that was my culprit, but it wasn't.
I've also noticed the car is occasionally hard to start - extended cranking of various lengths. Other times jumps immediately to life. No rhyme or reason to the hard starts I can detect - not temperature related, not related to how long or how brief the car sat. This morning after sitting all weekend it came right on. Some mornings I don't think it is ever going to start, some times it's in between those two extremes. I don't know if the two phenomena are related (surging and intermittent hard starts), but I'm thinking they are since there are no codes set - how many non computer/ non OBD things can be wrong at the same time?
Where to go next-
- I'm ruling out fuel pressure too low/failing fuel pump since it can sometimes start right up after sitting for days and days and sometimes struggle to start after being off for 10 -15 minutes
- I'm wondering if the cam seal under the cam sensor is as shrunken and brittle as the plug well seals were? Would oil screw with the cam sensor, but not set a code? And only do so when cold and whenever starting the car? I would have expected a code if the cam sensor detected it was out of sync with the crank sensor and ignition?
- Original HEGOs not warming up or responding quickly when cold causing really wacky rapid fluctuation in air/fuel charges? but I would have expected a code to be set.
- Some kind of short in the coil pack or DIS module that self 'heals' itself once it warms up? Seems far fetched unless it is actually a known failure mode for Yamahas.
- A novel transient failure mode for the crank sensor?
- Dreaded prior owner put in the wrong EEC IV computer module? (after all he gave me a J code CCRM, not D, to fix the low speed fan when I bought the car, and he never did the 60K service because he thought it was due at 100K) What code should be on the brain of a '95 MTX sold new in CA? This car does not have a EGR, but for some reason I thought CA cars all had EGRs...
Greg
Now 80K
'95 MTX - bone stock for now

 

[zoomlater]

When my car started bucking, it was the cam sensor. Did you check to see if there is oil leaking from the cam seal? You may want to replace it as it is not that expensive. Also be sure to check you don't have an extra orange seal already stuck inside the connector (it supposes to stay with the cam sensor). I almost gave up on my car until a read a post on here about two seals in the connector that caused intermittent problems.

Did you try unplugging the cam sensor and running the car, it make take a few tries to start.

 

[rubydist]

afaik, all CA SHOs came with EGR, both atx and mtx, so the "originally a CA car" story is suspect.

the random hard start is likely a loss of fuel pressure issue. typically its from a fuel pump check valve leaking but it could be from a fuel injector that leaks also. next time it exhibits the hard to start symptom, cycle the key switch to "on" for 3 seconds, back off, and repeat several times, then try to start. if it starts right up, that tells you that its a loss of fuel pressure issue.

a sick cam sensor can cause all kinds of havoc with how the engine runs. as zoomlater suggests, try unplugging the cam sensor and see if the symptoms change. you may have to try several times to get the engine to start, but once running the only significance of an unplugged cam sensor is that the tach will always show 0.

 

[black92]

Last summer I attempted to check codes. No luck. Turns out someone removed the CEL bulb.

 

[Greg Corcoran]

Hi all,
Thanks for helping out.
I had ruled out the fuel pump/ check valve since it can sit for days on occasion and still start right up, other times not. sometimes I can be in a store 15 minutes and it will be hard start. Is it possible for check valve to leak intermittently? I hadn't thought that was likely? BG44 fuel system cleaner might help clear any gunk in the injectors or check valve.
So what if this really IS a CA car and someone removed the EGR and replaced the back intake when the car migrated to IN? Would the EEC be trying to run a warm up sub routine program it can't execute? There is a extra connector at the firewall not connected to anything. But even then I should have a fault code set? Any place I can confirm what the calibration sticker on the computer case should be for an 95 MTX with and without EGR?
Cam sensor unplugging is where I'll start. I can also cycle the key switch on the next hard start just to see if there is any change.
Stay tuned.
Greg

 

[rubydist]

well, if it was a CA car and the EGR has been removed, then it will turn on the CEL every time once the car is warmed up, so that would likely motivate someone to remove the bulb or cover it up... yes, there would be a code.

yes, the fuel pump check valve can leak down intermittently especially if there is some dirt in the fuel tank.

 

[Greg Corcoran]

well, if it was a CA car and the EGR has been removed, then it will turn on the CEL every time once the car is warmed up, so that would likely motivate someone to remove the bulb or cover it up... yes, there would be a code.

yes, the fuel pump check valve can leak down intermittently especially if there is some dirt in the fuel tank.

Ok - so I think we can **** the former CA car/EGR removal theory - the calibration sticker on the EEC is "X2J" which I am nearly 100% certain was the code on my former '92 (which I bought new in IL, and it didn't have an EGR). Is X2J the right 'brain' for a '95 too? I would think three years later there would be a different calibration program.

I put a can of BG44 in the tank this morning to see if I can clean out injectors and check valve. Also today I cycled the key three or 4 times before every start and it always started right up. I'm going to do that a few more days. If I get no more hard starts during the next few days I'll need to change the check valve if a couple tanks with the BG44 doesn't fix it. Correct me if I'm wrong, but I believe valve is in the fuel pump assembly, So I need to drop the tank and change the fuel pump?

 

[rubydist]

X2J is a non-egr pcm code. the X2J will work just fine on any mtx non-egr SHO. there were several pcm codes, as you suggest, but they were interchangeable and I frankly don't recall any more which order they all came in...but the X2J was one of the middle/later ones.

 

[sperold]

The PCM that has the smarts required to monitor an EGR system is a X2Z.

You have the correct PCM for a non EGR car.

I would take a look at your cam sensor, and I would examine the grounding on your PCM.

This is a long shot theory, but if there was a state sales tax difference, could a bordering state buyer order a car in their own state and have it delivered to California (which could quite easily be the closest dealership). Sounds a bit odd, I know. But something is wacky about this; when an automatic car retains the EGR and the standard car does not...in California, no less.