Please Help! Experts needed for Automotive Forum

Well, I'll be right over.

Just as soon as I figure out why TFrog still doesn't want to run in the morning.

dwight

"dwight" wrote in news:mOWdnZYboZVnLZXYnZ2dnUVZ snipped-for-privacy@comcast.com:

Something new or the same issue as before?

Same old thing. Starts, but wants to stall out for the first minute or so. After that, runs fine.

I've worked my way up the intake trail, and now have a new map sensor, too. (At this point, I think my mechanic is guessing. Still, the CHECK ENGINE light is out for the first time in years.)

Next time in, I want to look over his shoulder at whatever codes are being reported. This is getting annoying.

dwight

"dwight" wrote in news:r9udnRPRm_feoZTYnZ2dnUVZ snipped-for-privacy@comcast.com:

OK, now I'm intrigued. If you force it to stay running, does it hold an idle after it's warmed up? IOW, does the symptom appear only when it's cold?

Speaking of cold, I just thought about it - 4/5 of the year our vehicles are never below 77 degrees, so they rarely run under the "choke" scenario. They almost always get to standard operating temperature within a minute or two.

Joe Calypso Green '93 5.0 LX AOD hatch with a few goodies Black '03 Dakota 5.9 R/T CC

Yep. Really takes only about 30 seconds, then I start driving. By the time I hit my first stop sign, it no longer wants to stall out.

It hasn't exactly been cold here, either (low in the high 50s lately). Even so, when you consider the temperature outdoors vs. the engine's normal operating temperature, what's 20 degrees between friends?

dwight

hell, neither do I. How early are we talking here? Once you retire and start getting up about 10AM that one will work its self out...

At the risk of sounding silly, I thought MAP sensors were for speed density cars???

I did some reading on the map, and all I found was that the vacuum hose need not be attached in mass air cars. Otherwise, it's in there (on both Frogs), hooked up, and must be doing something.

dwight

"dwight" wrote in news:VoadnbcNW667jpfYnZ2dnUVZ snipped-for-privacy@comcast.com:

OK, so it's something with what I'll call the "choke" circuit. Idle air valve? The thing on the distributor? Maybe the computer? Just guesses...

...maybe a light jacket or sweater? ;)

That might be the whole problem right there. It's possible that going on Daylight Savings Time will fix the whole thing.

It could just be that TFrog is not a morning car.

dwight

I jumped on the idle air bypass, since that made sense. Mass air sensor cleaned, IAB cleaned, throttle body cleaned... Now I've got all kinds of things running around my brain - vacuum hose leak, EGR, etc. The distributor was just replaced when the car wouldn't start at all last month. I'm afraid it's something really simple and really stupid, but I'd be happy if it was.

dwight

Does it go away once the winter blend of fuel is established? The oil companies add more lower molecular weight hydrocarbons (like butanes) to boost the vapor pressure at lower temperatures. They are starting to fill tanks with the winter blend now in northern areas.

Did it start this with the new distributor? Exactly when did it start? Does that correlate with anything else changing?

TFrog = '93 LX 5.0 stick, just passed 197,800 miles. The engine has never been opened.

In 2004/2005, it had major problems with the transmission, which I put off since we were moving. Once we relocated, I procrastinated for another several months before finally deciding on a transmission shop to do the work. They did a great job, and I now have all five gears back.

During that time, engine performance slowly declined into a very rough idle, and the car became increasingly difficult to start in the morning. I confess that I ignored this problem, focused on the much larger transmission issues.

Cleaning the mass air sensor is always a good thing, but it had little or no impact on the problem. But, immediately after cleaning the thing, the car wouldn't start at all. I had it towed to the shop, where the distributor, rotor, and ignition control module were replaced. So, the car runs once again, but is still difficult to start when cold.

Cleaning the idle air bypass and throttle body smoothed out the idle somewhat, but had no effect on the cold starting problem. The last "fix" was a new MAP sensor, which turned off my CHECK ENGINE light for the first time in about five years (several other shops couldn't figure that one out).

But the car still doesn't want to start when cold.

It starts, but wants to die immediately. Goosing the throttle for the first

30 seconds is enough to get the idle to where it should be, and then driving is no problem. After this, the car is still very healthy.

No problems whatsoever at higher revs (or WOT), and it will sit and idle all day once warmed. It's only that first 30 seconds or so...

dwight

"dwight" wrote in news:R_SdndWLKNYokZHYnZ2dnUVZ snipped-for-privacy@comcast.com:

Sounds like you've already hit most if not all of the obvious stuff. Computer maybe?