Wierd Problem(s)

[KMac]

I just started experiencing a wierd problem; maybe it's (2) problems.

About a week ago I noticed it was taking a longer amount of time than usual for my torque converter to lock up when I get to highway speed.

Yesterday, I noticed my idle speed while in gear at a stop was at 1100 RPM, when it used to be about 700 RPM. It still idles very smoothly, but it's idling fast for some unexplained reason.

In addition when I accelerate, the tranny now shifts to 2nd, 3rd, then 4th almost immediately after 3rd under normal acceleration, then immediately drops back to 3rd.


What the HE11 is going on???

BTW, I don't have a CEL on.

 

[Robert]

A good bet is that your thermostat is starting to stick closed. Take a close look at your temperature gauge and see if it is running a bit higher than usual. Another sure sign is that the idle doesn't run high until the engine operating temperature gets up to normal. My idle went up to 1100 RPM a week before I noticed my temperature gauge running at the upper end of its range. For a week my temperature wasn't running quite high enough for me to notice but my PCM bumped up my idle speed to acount for it to keep things cooler. After a week it was noticeable. I have seen a lot of '98 SOHCs lately with a stuck thermostat. Last year it was the '97s. Next year it will probably be the '99s and so on.

 

[KMac]

You may be right. Tonight I noticed the idle was indeed at 700 until the engine warmed up then it was at 1100. I didn't notice the temp gage, though. I'll check tomorrow. Thanks for the info!

 

[Spas]

A good bet is that your thermostat is starting to stick closed. Another sure sign is that the idle doesn't run high until the engine operating temperature gets up to normal. My idle went up to 1100 RPM a week before I noticed my temperature gauge running at the upper end of its range. For a week my temperature wasn't running quite high enough for me to notice but my PCM bumped up my idle speed to acount for it to keep things cooler. After a week it was noticeable. I have seen a lot of '98 SOHCs lately with a stuck thermostat. Last year it was the '97s. Next year it will probably be the '99s and so on.

That's always fun to get the bill for....they had to clean my whole fuel system after my therm sealed shut-apparently most of the fluids bottled up under my front seats or somesuch. That and the friggin' O2 sensors that keep going up :fire: . They've been responsible for the idling probems on mine, Kmac-you may want to have them checked as well.

 

[KMac]

On the way to work this morning I did verify the thermostat was sticking. It would get all the way to the "H", then crack open. Robert hit the nail on the head. Gracias!

 

[Robert]

You're welcome. glad it's something simple. Not even my Ford dealer knew that the high idle was due to my thermostat sticking closed. I originally brought it in to them when I noticed the high idle that I had for the last week. They couldn't find anything wrong and had no idea why my idle was high. I disconnected my battery the day before taking it to them to remove my SuperChip so they didn't try blaming the idle on it. By disconnecting the batter, I cleared the drive cycle parameters. Since they weren't in the computer, the Tech didn't know what to do other than tell me to come back in a week after I have completed a complete driving cycle. It was on my way to work the next morning when I had my OBD-II scanner hooked up that I noticed my temperature running at 240F. Looking at my needle verified that it was maxed out. I drove straight back to the dealer and told them that the temperature was now running hot. Anyway, some argueing back and forth, they agreed to let me leave it again and after more hastles they found that the whole problem was caused by my stuck thermostat.

It's strange that the only ones I see right now with the problem with any kind of regularity are the SOHCs. Like I said, last year was the '97s, this year is the '98s. I guess when my idle starts running high in three more years, I will know what the problem is. I won't be putting a Ford thermostat back in then now that I know they fail at regular intervals.

 

[Spas]

I won't be putting a Ford thermostat back in then now that I know they fail at regular intervals.

I was so angry at the time that I got my thermostat replaced that I didn't even think to ask if there were other brands available.... Who else makes them and which is the best? Do you guys ever hear of fuel pump failures for the SOHC?

 

[KMac]

Robertshaw is a pretty big supplier of thermostats. I actually replaced mine last night with a AutoZone brand thermostat. Oddly enough it is made in Germany, which is what it said on the back of the original Ford piece I took out.

FYI, at AutoZone the counter monkey informed me they didn't have any of the gaskets in stock, so use blue RTV. It turns out there is no gasket, but an o-ring that comes with the thermostat. Whole job took about an hour and I was taking my time, yelling at the kids to get out of my tools, etc.....

 

[Robert]

It's good to hear that the Autozone brand comes with the o-ring. How much did it cost at Autozone? I knew that the thermostat used an o-ring instead of a gasket. I just didn't know if it came withthe o-ring. I would never have used RTV sealant on mine. Don't put too much credit in to what the auto parts store counter monkeys have to say. It's OK to listen to them, but be willing to confirm their answers with another source. This group has been one of the best sources by the way.

 

[KMac]

AutoZone thermostat was $14.99.

I returned the Blue RTV unopened.

I usually don't even ask the counter monkeys, but my thermostat wasn't out on the floor, so I had to ask him to get it from the back.

Having now seen the thermostat housing design and o-ring, this is the best housing design I've ever worked on. No gasket, no RTV, no way to overtorque it and break the flange ear off (like when using a gasket), etc...

 

[Spas]

Counter Monkey...I've never heard that one before, LOL

Thanks for the info,guys. I guess I know where to get a new Thermostat the next time mine goes up