I have a 1994 Aerostar with a normal (not high) idle when it starts cold.

[94 ford]

I think I have my own problem with my Aerostar. It is a 94 short E-4WD 4.0. I have only owned it for about 3 months, it now has 58,000. Since I bought it I have (New plugs, wires, PVC, cleaned MAF, changed all fluids, new thermostat, old one was sticking open, to try to correct idle problem replaced TPS and idle air control valve, after doing all this it idles alot better. The problem or wierd thing that it does is, it seems to not go into cold idle mode when it is started cold (sitting overnight) When I start it, it idles like it has just been driven. I have owned alot of fuel injected cars, and they always idle high for a little while when first started when they are cold. So I know this one should to. It still idles a little rough until it warms up. I have checked for vacuum problems, don't see any. Any sugestions, I am getting tired of playing (Which sensor is it game) (HAHA) Any help would be appriciated, can any one with the 4.0 let me know how theres idle when cold? I know this is not an Explorer, but I could use all of your knowledge on the 4.0 this is driving me nuts!!!

 

[Alec]

First of all, welcome to the site!

Sounds to me like it's either 1) a computer problem, or 2) something to live with (sorry).

It could be a problem with the computer. Have you reset the computer lately? This involves disconnecting the (-) battery lead for about 10 minutes, then reconnecting it and letting the car idle in park with no accessories for about 10 minutes.

Otherwise, is the van drivable? Are there any problems after you put it in gear and drive off? If the car is otherwise fine, and resetting the computer didn't work, I don't know what it could be. Mine does this sometimes, but is fine once I put it in gear. It might just be due to outside temp changes. The only other sensors I can think of that might contribute to the problem are the O2 sensors...

Hope this helps!

 

[kps36]

I agree w/Alec. I have been through all the things you mentioned with both the Explorer and my sons 95 Ranger. The first thing you need to do, if you haven't already, is purchase a manual. The Haynes will suffice for the level of mechanic I am. The basics and little more. Chiltons is better and elevates that level when you are ready to tackle the biggies like rear end changes...I just want them to run at a top notch level.
That said, I was kinda curious as to why the Haynes manual said in the first step of most of the maintence items was 1)disconnect the negative battery cable.
I have done most everything you have listed and they all solved an immediate problem. I even disconnect the cable when I change oil, and at the same time..clean and reoil the K&N, spray off the MAS, clean the TBody. Reconnect, and it runs like brand new again.
With all that you have done/replaced, I would say reset the computer. I hope you replaced the IAC valve/sensor rather than just cleaning it. That worked for me for about a week, then I had to replace it, solved my idle problem on the Ranger. If you are not 'throwing codes' (CEL Check Engine Lite ON) my first 'shade tree mechanic' instincts say recheck the plugs/wires.

 

[94 ford]

Thanks Alec, yes I have disconnected the battery each time I replaced a new sensor. The van drives fine with plenty of power and never has died on me. No check engine light either. I am presently getting 17 MPG which I think is pretty good for the wieght of the van and the E-4WD system.

 

[94 ford]

Thanks kps36, I did install a new IAC. I was also wondering if maybe it could be the temperture sensor for the computer, the one mounted above the thermostat. Maybe the ECM is getting wierd info from the temp sensor. I do have the FSM on disc that is great. BTW if any of you need any info from it just ask, it is for 95 models, and covers everything with the 95 light and heavy duty trucks.

 

[tac0meat]

i know this wont help you at all, but i was just curious, you say the van has the E-4WD system, does that mean it has 4wd? if so is it with a transfer case (2hi, 4hi, 4low)?

 

[kps36]

you're welcom and WELCOME to the board (I forgot the first time) BEST ONE AROUND !!

That is very much a possiblity. That sensor is so easy to get to and cheap enuff (@$30) that I changed on both vehicles when I did the TStat (still hasn't solved the low temp Gauge problem on the Ranger, that's a different sensor, but I know at least the PCM is getting good info).

 

[94 ford]

tac0meat, it is really AWD. The emblems on it say Electronic Four Wheel Drive. It is all automatic you don't do anything but drive it. It has a Dana 28 Transaxle, and delivers 1/3 power to the front wheels all the time and increases it when it is needed.

 

[Triton46]

Are you getting decreased fuel economy?

 

[tac0meat]

ok, if it was true 4wd you ought jack it up, put some boggers on it, brushgard, and all the other must-have's. it would be cool though cause there arent too many vans that can go rock crawling.

 

[94 ford]

Triton, I get about 330 miles to 21 gallon tank. Tac0meat I will have to consider that, I can just see my 5 foot wife cruising around the hills in that modded up Van. (HAHA)

 

[94 ford]

Thanks for everybody's help, replaced the ECT and solved the problem, plus seems to run much smoother.

 

[kps36]

Hey 94 Ford...
You mentioned you have a 95 truck FSM on disc. I have a request to look up a Ford PN on a Ranger...Email me at
kps36@hotmail.com
Thnx, BTW, what exactly is a(n) ECT ?
thnx again.