'82 automatic cutting out and dying when outside temp is hot

[BoiseShark]

My son's 82 is having problems. It has been hot here in Idaho this summer and the car will run fine around town...well, died once, but when he takes it out on the highway, it will run for about 30 to 40 miles and then it will start to cut out and quickly die. After this happens, he can wait at the side of the road for about 10 to 15 minutes and it will start up and drive again. Then it will run for about 10 miles and do it again. Finally, you have to wait 15 minutes for one mile worth of running.

It is like it is vapor locking but I have driven it without the gas cap on (I don't know if that really is a solution to vapor locking...Just what i've heard)

It also acts like it is chocking out but there is no black smoke coming from the back end. I've had a car that loads up before, not a 928, and it will start to really puff out black smoke from the exhaust.

If he runs it in the morning when it is only about 60 to 70 degrees out, the car will run those distances fine.

Does anyone have any ideas or any tests that I can run?

Thanks guys

[harborman]

Well, I have a 86 so different. Mine does have some temp sensors up near the front of the manifold. Someone with a 16 valve should be able to help.

[JhwShark]

Interesting issue...I do not know your MY '82 and I have a CIS.

However, I would be inclined to look at the fuel accumulator (FA) starting to fail. A failed FA, can have similar symptoms; but, I never had them while driving only after stopping.

[BoiseShark]

I'll look into the fuel accumulator. My 82 is a 1982 928 with the 4.5 liter.

Does anyone think a fuel filter would be worth looking at? Will simply driving with the fuel cap off solve a vapor locking issue?

I wish there was a 928 mechanic here in Boise or anywhere in Idaho for that matter. This one is beyond me. I can't figure it out.

[The Deputy]

I'd check the fuel pump relay first, maybe even have the CE panel exposed and a new relay ready, so when it happens you can change the relay and see if it makes any difference. Other areas I might suspect would be (with info supplied and not knowing which system is failing), fuel pump, ignition coil or ignition module.

Good luck, and don't give up. Just try too determine which system is failing, fuel or ignition...that would help immensely.

Brian.

[JK McDonald]

Hey BoiseShark - It will also help in diagnosing your problem to know how long you've owned the car. Did you inherit this stalling issue or did it develop over time ? You might "T" in a simple pressure gauge to observe the system fuel pressure as the shut down occurs to determine if the stall is fuel related or on the ignition side of things.

Just a shot in the dark but - it sounds like a lack of fuel quantity or a supply problem (filter or fuel pump) since you indicated that the stall repeatedly occurs when out on the road. In town the volume of fuel to your injectors may be supplied sufficiently at slower or stop and go speeds.

Here is a typical test gauge set-up with all the fittings needed to keep a Bosch CIS car running happily. If you plan on a long term ownership they are worth buying.

Save on ATD Tools 5567 at TheToolWarehouse.Net

Sorry short between the headsets for a moment - here is the correct CIS test gauge set. There are probably other examples for a better price.

http://www.amazon.com/CTA-3420-Jetronic-Injection-Pressure/dp/B008FJXA3M

Keep us posted - Michael

[BoiseShark]

Thanks for your help guys. I've had the car for about 2 years now and the problem just started this summer.

It's actually not CIS (luckily)...lol

I will check into these possibilities. I can actually use the pump relay from my 84 to test that.

I'm getting closer with your help

[JK McDonald]

Sorry - I thought there was a reference to a CIS system. At the end of the right hand fuel rail on the L-Jet injection there is a removable cap so a fuel pressure gauge can be temporarily installed. This will allow you to monitor the pressure as the stall occurs. One note though - there is a small metal ball under that cap used for a seal. Watch for it as the cap comes off. I usually spread a cloth under the fuel rail in case the ball gets away from you just as a precaution.

One other point - you need to hold or support the fuel rail steady as the end cap is removed so you don't damage the rubber fuel lines/connections headed to the injectors. It sometimes takes a considerable amount of torque to initially loosen the cap from age.

Good Luck - Michael