98 SOHC Cold Start Idle problem

[mikeh]

I'll start one more idle problem thread .

I've been having problems with my idle when I start after the truck has sat overnight and the tempeture is cold out. Here is what happens. I don't touch the accelerator at anytime while starting the truck. I crank it over and it starts right up and the idle jumps to about 2K. Then it starts idleing back to about 500RPM then it jumps down to about 300rpm and almost dies and then it settles down to about 400rpm and stays there almost dieing the whole time. If I throw it into gear then the truck sometime will die and other time will kick the idle up a bit and I can back out.

Once the truck is warm everything works perfect.

I have 80K miles on this 98 SOHC 4.0 Liter X.

I've read all of the threads on the IAC valve and thought that was it but I was wrong. Here is what I've done so far.

Replaced the battery.

Replaced Plugs and wires with new Motocraft parts.

Replaced the IAC Valve.

Cleaned my MAF thingy.

From all of the posts I've read I have a small list of things it still might be I'll list them for discussion.

1. Lower intake manifold gasket?
2. Reflash PCM?
3. Clean Throttle body?
4. Throttle position sensor?
5. Cam Tensioners?

I've had the truck since new and I had too many miles to get the plastic chain guides replaced under recall.

Any thoughts on this are greatly appreciated. And I think I have read every thread on the subject in this forum.

Thanks,
MikeH

=Post 33 has the solution =

 

[daniel cauchon]

Dont worry about your number 1 issu it`s definitly not it !

I would go for 3. Clean Throttle body for now, and one more thing is the injectors, I would clean them too.

 

[fvumbaca]

i can almost garentee its the manifold gasket...i have the same exact truck i bought mine last year with 35k and around 45k winter came around and everytime i started my truck it would surge like you described and then die down and if i didnt get it moving fast enough it would die completely....this is what happens...in the cold weather the gasket shinks causes a gap...when the truck heats up it returns to the right side and the problems disappear...the good news for me it was a volenteer recall from ford and i payed nothing for the repair...if i where you i would get it fixed before it gets below 20 degrees or so because trust me that will cause a serious problem trying to get moving...i can almost garentee its none of the other things bacause i didnt clean any of that stuff till this summer and mine where in pretty bad shape

 

[Robert]

It is your lower intake manifold o-rings. You are outside of the warranty to get them replaced at no charge as well as the camshaft tensioners since they are only covered to 72K miles. You are not out of warranty though to get your camshaft chain guides replaced if they are making a loud rattling noise. They are covered for 100K miles.

 

[mikeh]

Robert,

Thanks for the chain guide advice. The dealer had told me that it was 72,000 a while back and I was at 73,000 at the time.

Since there seems to be a discrepency in the posts as to my lower manifold gasket is there a test I can run to determine if it is leaking?

Thanks in advance,
mikeh

 

[fvumbaca]

the way they found out the problem on my truck was the check engine light was on...they hooked it to a comp..the dianostic came back with that...i dont know the code off hand....one thing i would suggest doing is at autozone (at least the ones near me) they do diagnostics for free, in an attempt to sucker you in for service....it might be worth doing so you know the exact problem so you can get it fixed

 

[fvumbaca]

oh just to let you know for ford to check my gasket and replace it it only took 45 minutes...just to let you know if you wanted to attempt it yourself

 

[Robert]

When I determined that my o-rings were leaking, I used Ford's procedure that they described in an older TSB from a few years ago (I don't remember the number). It involves using an OBD-II scanner to monitor your short term fuel trims and then spraying propane around your lower intake manifold. If you see a sudden change in the short therm fuel trims, you have a leak. Do it when your engine hasn't been run for at least 8 hours so the leak is the most severe. It makes the fuel trim change more drastic and easy to spot. Ford has since updated the TSB to reference the procedure in the Ford Service Manual so the procedure is no longer in the text of the TSB now.

 

[section525]

They replaced your head gasket in 45 mins? Is that what you're talking about? The manifold head gasket?

 

[fvumbaca]

they replaced the leaky o-ring in 45 minutes

 

[section525]

So was the manifold gasket your problem too, or just the o-rings? Where are these o-rings? (Sorry, I'm foreign to four ohs).

 

[fvumbaca]

sorry about that...they replaced the o-ring and that fixxed the problem...i dont know where it was...i didnt hang around for the repair because they originally told me it was going to take 2.5 to 3 hours....they ended up calling me before i even got home

 

[section525]

I think it is a recall deal. # 00M12. I used the search button Robert, that recall fixes the o-rings, right?

 

[mikeh]

Yep it's 00M12 recall. Unfortunetly it runs out at 72K and I now have 81K and I just called the dealer and he said it was about $400 for the fix. This really PO's me as I was complaining about this problem back at 75K and they told me they can't do anything for me. Now with the O-ring problem I'm going to have to get it fixed. I still don't know if I want to tackle the problem myself. I'm trying to get a handle on what the parts would cost if I do it myself. Not quite sure of all that I will need for the repair yet.

mikeh

 

[Robert]

Originally posted by fvumbaca
sorry about that...they replaced the o-ring and that fixxed the problem...i dont know where it was...i didnt hang around for the repair because they originally told me it was going to take 2.5 to 3 hours....they ended up calling me before i even got home

I doubt if they replaced the lower intake manifold o-rings in 45 minutes. They probably found another leaking o-ring (probably under the IAC). Mine was also leaking when my manifold o-rings were leaking. If they did the o-rings, they did it in about half the Ford book time. If it was done within the last 2 years, then they should have also replaced the camshaft tensioners since the TSB instructs them to replace both if either fails. That would bump it up to about 2.25 hours of book time for the complete job.

 

[Robert]

Originally posted by section525
I think it is a recall deal. # 00M12. I used the search button Robert, that recall fixes the o-rings, right?

It's not a recall. It is an Owner Notification Program. In other words if the parts have failed under the mileage/time limits of the ONP, Ford will replace the faulty parts at no charge. If it were a recall, Ford would replace the parts whether they failed or not. Recalls also rarely have a mileage/time limit. We are still getting recall notices for my Wife's '93 Sable for the TFI and head light switch. And yes, ONP 00M12 fixes the o-rings (and tensioners).

 

[Robert]

Originally posted by mikeh
Yep it's 00M12 recall. Unfortunetly it runs out at 72K and I now have 81K and I just called the dealer and he said it was about $400 for the fix. This really PO's me as I was complaining about this problem back at 75K and they told me they can't do anything for me. Now with the O-ring problem I'm going to have to get it fixed. I still don't know if I want to tackle the problem myself. I'm trying to get a handle on what the parts would cost if I do it myself. Not quite sure of all that I will need for the repair yet.

mikeh

It's not a recall. It is an ONP which basically extended the warranty on the parts if they fail. Go to an independant shop if you choose not to do the o-rings yourself. My local mechanic only charged my extended warranty company $130 to replace the lower intake manifold o-rings before the ONP came out.

 

[fvumbaca]

they told me they replaced the o-ring....unfortunetly i'm not home but when i return on thursday i'll look up the bill and find out exactly what they did...and it was less then half a year ago

 

[pmahoney]

I have the same cold idle problem and have had it since long before 72K (I'm at 106K now). It irritates me that I could have had this done earlier.

Where can I get access to the "TSB's" I hear so much reference to? I tried to get a copy of one from both Ford and my local dealer and neither was a bit of help.

It seems to me that Ford has a responsibility to communicate known problems to owners in a reasonable time period.

 

[Robert]

I get my copies via my subscription to Alldata (www.alldata.com). Ford did communicate the o-ring to owners back in November, 2000. At that time they sent letters out to all known owners advising them of the extended warranty that was good for 6 years, 72K miles. In the letter it also stated that there was no mileage limit through April 30, 2001 so that people that had already put more than 72K miles on their Explorer could still get coverage.