Cam position sensor

Well, got it done!

Details to follow on the install but It's still throwing the code! New sensor and new synchronizer, what else can it be?! I haven't driven it yet because of the weather, but I'm lost now. :bawling:

Joe
Dumb question, did you clear the code after the repair?
 
I did before I started working on it.

Joe
 
Joe, sorry if this is another dumb question...

Did you check all the wiring (continuity) and shielding between PCM and sensor.

In my case, all that was intact, but I did a lot of cleaning of terminals in the process.

You can check that in two parts:
- between sensor and that large connector on the firewall near the antenna
- between that connector and the PCM connector

I have the diagrams for those connectors if you need them.
 
Martin,

No actually I didn't. I "was" just happy to get it back together and it started right up. Thing runs great but you were having problems with the stalling weren't you? Tomorrow is supposed to be a decent day so I need to get this out on the road, maybe some miracle will happen and the codes will reset.

Joe

No problem asking questions, I'm all ears!
 
I meant as far as cleaning the connectors, you were getting the crankshaft code. Which led me to buy a new crankshaft sensor....just in case! :biggrin:

Joe
 
Which led me to buy a new crankshaft sensor....just in case! :biggrin:

I mean it can't hurt.

But I don't like throwing money at things unless they make a difference. Replacing the sensors did not resolve my code, so I went back to my original sensors.

If you remember, ultimately I couldn't identify what exactly resolved my code. Possibly cleaning all the connectors, plus I regapped all the sparkplugs.
 
Try clearing the code again, and see if it comes back right away.
 
Try clearing the code again, and see if it comes back right away.
It did! :mad2:

My turn for a dumb question. If by chance I didn't get this lined up 100%, would that cause the code? I would think if it wasn't right, it wouldn't start at all.

Back to what I asked earlier on, do I need to drive this to get the code to reset? OK, two dumb questions!

Joe
 
If you have cleared the code you shouldn't have to drive it to reset. It is possible for it to be misaligned and still run. So it is possible that it could be misaligned and cause the code. Is there noticeable play in the shaft on the old synchro?
 
The only play in the old one is up and down, not much but it does move.

I marked the block where it was aligned and took pictures of the half moon location. Then I unbolted it (that was a bitch!) and attempted to pull it out, wasn't budging. Being an almost 26 year old it needed a little more muscle, bad move! It came out a little too far for me to get an exact mark on where the half moon would end up. So I just installed the new one in with the half moon in the same position and the body of it lined up with the marking I made on the block.

Joe
 
Gotcha, Is the sensor pointed in the same direction it was before?
 
Yes sir, both sensor and synchronizer are positioned the same way.

Joe
 
Did your new synchro not come with the alignment tool ?

I used to have a good diagram for the sensor alignment .. the one in the shop manual isn't very helpful, but I will keep looking.

I remember something about setting the timing to 26 degrees ATDC and aligning the vane with the mounting bolt for the synchro to timing cover. It's been a while since I've installed one of these.
 
It didn't Dan.

Joe
 
This looks very similar to the explorer 4.0L OHV synchronizer, except the explorer sync is located at the very back of the block instead of the front on the 3.8L?
 
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So I took the car out for about a 40 mile road trip up and down the highway and it ran like a champ. Speeds between 65 and ?? and not a hint of an issue. Got it home about 45 minutes later and did a scan, code is back.

Should I try another sensor? Martin recommended started cleaning connections, I'm open for any recommendations right now. I don't know what else it could be.

Joe
 
So I took the car out for about a 40 mile road trip up and down the highway and it ran like a champ. Speeds between 65 and ?? and not a hint of an issue. Got it home about 45 minutes later and did a scan, code is back.

Should I try another sensor? Martin recommended started cleaning connections, I'm open for any recommendations right now. I don't know what else it could be.

Joe
Any chance you have a spare computer to swap in? My Green 97 had a p0340 code when I first got it that turned out to be a bad PCM.
 
At this point it has to be bad wiring, connectors or the pcm itself. Start with the connectors, check the continuity of wiring, or scope the signal at the PCM.
 
At this point it has to be bad wiring, connectors or the pcm itself. Start with the connectors, check the continuity of wiring, or scope the signal at the PCM.

I agree.

The challenge is that the wiring may only lose continuity while driving (e.g., due to vibration); so testing for continuity at standstill may not reveal any faults.

Nonetheless, such testing is what I'd do next.

Remember to test "both ways", meaning test for continuity where it should be, but also confirm absence of continuity where it shouldn't be.

Swapping in another PCM was part of my diagnosis plan, though fortunately my code was resolved before I got there. Good thing because V6 PCMs aren't easy to find; most cars I see in yards are V8s. What was the V8 take rate when they were new?


Joe, could you clarify: at this point, there are no drivability issues at all, correct? Meaning that you have no symptoms other than the code? No misfire or hesitation?
 
Any chance you have a spare computer to swap in? My Green 97 had a p0340 code when I first got it that turned out to be a bad PCM.
Unfortunately no, your 97 is a 4.6 car isn't it?

At this point it has to be bad wiring, connectors or the pcm itself. Start with the connectors, check the continuity of wiring, or scope the signal at the PCM.
I was afraid this might be the issue, I'm a total noob when it comes to wiring issues, I don't even have a voltmeter. :sad: Dan, are you talking about doing live data?

Joe, could you clarify: at this point, there are no drivability issues at all, correct? Meaning that you have no symptoms other than the code? No misfire or hesitation?
Martin, the original issue seems to taken care of. That happened when I put the new sensor in. The car runs great, no issue other than the code. I mentioned earlier when I was changing it, that the clip on the connector broke :mad2: and I taped it up pretty good to hold it in place. I might start there.

Unfortunately, I might not be able to get to this right away. I'm flying out to Denver next week for Thanksgiving and I have have a ton of stuff that needs to get done around the house before we go. It will almost be December by then, so this might go on the back burner untill spring.

Joe
 
Yeah, mine is a 4.6
 
The tune itself wouldn't be fully optimized but a 96-97 V6/auto Mustang PCM will interchange, those might be easier to find in a junkyard if you just wanted to find one cheap to test
 
The tune itself wouldn't be fully optimized but a 96-97 V6/auto Mustang PCM will interchange

Whaaaat?! I didn't even think about that. Sounds like an interesting mod: just swap in a Mustang PCM and gain revised shift points? Could be good or bad.

They're definitely easier to find.
 
Any junkyard runs in your future?! 😬

Joe
 
Whaaaat?! I didn't even think about that. Sounds like an interesting mod: just swap in a Mustang PCM and gain revised shift points? Could be good or bad.

They're definitely easier to find.

I wouldn't do it for a mod, shift points can vary swapping one box code 96-97 Tbird PCM to another too, Ford tended to change that with updates. But yes, its the same physical hardware and in V6/auto(or V8/auto for that matter) they will work in a Tbird application, plug and play. for this purpose of diagnosis it could be useful.

Fan settings may vary and the MAF transfer function may be different as well, though you could probably swap them
 
Yeah, the point would be to swap in the computer, take a drive and see if the same code comes back. If it does then you recheck the work done and check wiring. If it doesn't come back, get another Tbird PCM.
 

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