I noticed that it *does* start right away when it's hot. But only if you let off the key shortly after it starts to crank. Then it idles real low (200rpm) and sometimes catches, sometimes dies.

This sounds like a starter that gets weak when it gets hot. Anyone agree?

 

New starter, ECT, MAP. Still same issue, takes many tries to start when hot. Sometimes more, sometimes less, but always much harder than when cold.

Also don't know where to install IAT, and have TPS coming tomorrow.

Thanks,
Chris

 

Subscribing....

My fathers 1995 does the exact same thing. Is there much of a difference between these years?

Jason

 

The IAT or ACT, it is called both and is the same sensor.

IAT = Intake Air Temperature sensor.
ACT = Air Charge Temperature sensor.

The location of the sensor on a 1990 and I think that the 1989 is in the same place:
http://i54.photobucket.com/albums/g9...98975151-6.jpg

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You should start you own thread.
That said what size engine does your father have?
Is your fathers a car or a truck?
Is it a Ford?
If yes to the last two above are truck and Ford then yes they basically use the same strategy in the EEC-IV Computer Module. They are also called the ECU, EEC and PCM Computers depending on the application.

ECU = Electronic Control Unit or Emission Control Unit depending on the year.
EEC = Electronic Engine Control.
PCM = Powertrain Control Module.

 

[quote=subford;7450429]You should start you own thread.
That said what size engine does your father have?
Is your fathers a car or a truck?
Is it a Ford?
[quote]

I appreciate the help, but why would I even bother "subscribing" to a thread that has nothing to do with my father's vehicle?

If it's not a Ford, why would I be here?

It's an 1995 F 250 4x4 w/460. So, it's the same motor, just a 1995 version. It also has the same issues.

Please advise if I need to start a new thread, as I don't wish to hijak this one.

Jason

 

Others have had similar problems with other size engine and transmissions and will ask in a Thread they find handy.

Others have, they may own a Ford Truck and want ask about another vehicle and did not want subscribe to another Forums.

Some of the posters on here will read the start of a thread and not want to help on that one for some reason so when they see it again they will skip over it. If you post in that thread then they will never see your post and not help you. If you find a current Thread just like you would post then you can set back and read the mail.
Have you done a search?
If you can not find what you need reading the mail or in a search then yes I would start a new Thread.


The bottom line is do not make us guess what you have and what you have done to it to fix the problem
already.

 

A little more information:

I took it in to a shop on Friday morning, and they replaced the original ignition control module and put a new pickup in the distributor. They also fixed a loose ground to the computer. They checked every sensor and said every one was good.

The hot-start issue is improved, but still there. There's a TSB out that they said probably addresses this (TSB 89-24-9), but that says to replace the computer with an updated one. Ford dealer said they stopped making that computer 4-5 years ago, and the NAPA computer they tried had the exact same behavior, so probably was the original programming, not the one in the TSB.

I guess the problem is that the computer's strategy with high engine temps is to retract the timing, which makes it hard to start.

Does anybody know how I could work around this, or how to find the updated computer somewhere?

 

What is your Calibration number?
It should be on the door post.
Also what is your Built Date?
Do you have a Manual or Auto transmission?
If it is an Auto what type transmission?
How many pass is your radiator?
Do you happen to know what your Thermostat Temp. is?

Did you ever replace the ACT/IAT sensor?

This sensor will test good in the self-test but can be bad and cause your problem.

IAT = Intake Air Temperature sensor.
ACT = Air Charge Temperature sensor.

 

Calibration number is 8-98A-R10.
Build date 11/88.
C6 Auto trans.

Don't know any specifics on the radiator or thermostat temp, but I've never seen it overheat, and it only goes maybe 1/4 of the way on the dash temp gauge. But my voltage gauge is known to be way off, so maybe the temp gauge is too?

I did not replace the ACT/IAT sensor, since I didn't have the right deep-well socket to get on it. Supposedly they had some kind of 60-pin breakout box they used to test the sensors? I don't know if this is different from what the self-test says. Should I replace the IAT and TPS anyway?

EDIT: What should I count/read to tell you about the radiator/thermostat? The shop said they're out of ideas (without the new computer), so you guys are my last hope! It runs "good enough" now, but there's no reason it shouldn't run like new.

 

The computer you want has a number on it = F0TF-12A650-AVA (The number Auto Parts Stores go by and salvage yards).

If you search the web then use F0TF-AVA as they do not use the base number 12A650 to save space, all computers have the base number of 12A650.

The Ford part number was F0TZ-12A650-AVA, this number is not put on the part, only used by Ford.

Here is one that I found online:

http://ww7.aitsafe.com/cf/add.cfm?userid=9764234&product=Computer%2078-4888%20Core%20Charge%20$70.00&price=226.85&return= acdelcocomputers.com

This image is below.

OR their URL was:
Ford Computers , Control Modules, F07F-FA - F1ZF-DB ,pg4

I am sure their are trucks in salvage yards with this number as this computer was more than likely used in the 1990 to 1992+ trucks also.

Most auto part stores should be able to sell you one also when you give them the F0TF-12A650-AVA number.

B&B Automotive Parts:


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Besides the computer you will also need a new Silencer, I would guess off a 1990+ truck with a 460 engine in it.

Do you have the TSB on all of this, if not email me and I will send you the TSB in a PDF.

Note that the they all so change the thermostat on some of the trucks maybe to a lower Temp. one and also change the Silencer.

If you do not have a four pass radiator on it I would change this also as they seem to want to lower the temp of the engine in the TSB.

But as I said above your problem may only be the Air Temp sensor.

 

So this is a problem all people with 460's have? Well I have it obviously. Is it really necessary that we fix this hard start when hot problem? Because, my truck always starts when hot it just takes longer. If it is not fixed will damage occur to the engine over time?

 

Let us know what finally fixes the problem.

 

No just some of the 1988-90 with Calibration numbers that are in the list.
That would be up to you.

Maybe if the engine is all ways running hot.

The computer change and the other modifications is not for the starting part it is for the running hot part. This is to make the engine run cooler.

They are saying a hot engine will be hard to start.