Howdy,

our '93 3.0 Aerostar has started acting up in the (now) cold mornings. On the first start, she stalls. Sometimes we have to restart several times before the engine keeps running. Idle is a bit rough, after a minute she runs fine and starts perfectly during the day, even when cold. Any ideas?

Tom Ucen
Munich, Germany

 

Hi Tom, good to hear from you again.

Since your engine runs fine after starting, there may be a problem with one of the EEC temperature sensors feeding false info on start up giving either excessively rich or lean mixtures. I would look at the air charge temp sensor on the intake first. Pull that, put a meter on the lead, apply low heat to the tip and see if you get a corresponding change in resistance. It should decrease in resistance as the tip warms up.

The engine coolant temp sensor can be tested in the same way although some coolant will be lost when removing the sensor. You can drain drown about 1/2qt(500ml for you metric Germans) beforehand.

As a frequent poster, you are undoubtedly aware of the common MAF and IAC problems. This doesn't sound like either of those but a shot of cleaning fluid may not hurt.

Any driveability problems when first starting out in the morning?

All I can think of at the moment. Hopefully others will have additonal thoughts on this problem.

 

Hi Aerocolorado,

thanks for the hint. I'll check the sensors on the weekend. I sort of figure the problem about the intake air temp because as soon as the intake air gets warmer (choke effect) she runs fine.
I pulled the codes recently and found a defective TPS. Replaced it and now the engine runs better when cold. I replaced the MAF sensor a few years ago, but it's a good idea to clean it.

Regards,
Tom Ucen
1993 3.0 Ext.
Munich, Germany

 

Once again information I found on this website has solved a problem that had the Ford Dealership and my mechanic scratching their heads for the past five months.

My '93 Aerostar has had a rough summer, first it was having problems with stalling at whim... which was solved by replacing the spark plug wires (thanks to info I found here)... and then there was the worsening problem with erratic idle causing it to stall when I started it after it had been sitting for some time.

I took it to the Ford Dealership for that one (figuring they should know their vehicles). They put it on some scope and eighty dollars later told me they had no clue what the problem might be, and I would need to leave it with them so they could leave it on the scope for four more hours. Seems to me leaving a vehicle that has problems starting on a scope for an extended period of time would tell you nothing... (but I am not a certified Ford Mechanic, so what do I know).

Anyway... I found the information here about the MAF and IAC... and took it to my non-ford mechanic. He first replaced the MAF... no difference, and yesterday the IAC and voila the van started just like it used to when it was new. Hurray and thanks again for the information.

(I also had to replace the rear tailgate latch, and the rollers on the passenger door this summer... funny how ten years can cause things to go all at once).

best regards,
Steve Hume aka CalgaryAerostar

 

I fixed the problem in the end by changing the idle air valve. I incidently had one on stock so I figured I'd give it a shot. No starting problems ever since, the wife is happy now.

Tom Ucen
1993 3.0 Ext. 91k mls
Munich, Germany