Hi everyone,

I'm new to the board, and frankly only found it because I have a problem that stumps me.:

I have a 95 F150 302/ Auto OD about 150k on it. Has run perfectly until recently. Now, it will start, and run perfect for almost exactly 5 minutes, then die. Usually will not restart for at least 5-10 minutes, but on 1 occasion it would not start again until the next day. This has occured every time I have started or driven the truck this week. It will behave the same whether I drive it or just idle it in the driveway.

I have fuel pressure at the rail the entire time. Plugs are less than 5k old, coil, cap, rotor, and wires were replaced with the plugs. Fuel filter was done about 8k ago. Vacuum pressure looks ok until the truck dies. KOEO coding pulled a code 33 (EGR failed to open, I believe). I have checked and have vacuum at the EGR, and the sensor is testing good on my VOM. Any ideas?

Thanks in advance

 

If that's not it, get a Haynes manual (PN 36058) & follow the ignition diagnosis in Ch.5 Sec.5 on p.5-5.

 

No problems found in the harness, but thanks for the tip.

I went through the ignition diagnosis again as you had suggested. Only thing that was out of spec at all was the secondary coil resistance. It read out around 5800 ohms, instead of the 6000-14000 specified. I switched from the Chinese coil I had put in a while back to an OE one, but the OE coil also read secondary a little on the low side, so it may be my multimeter that is causing the error.

Subsequently, the weather has warmed up, and the symptoms have disappeared. I am suspecting there may be a cracked solder joint somewhere(if changing the coil didn't fix my problem), but I am open to any other suggestions.

Thanks

 

Install a new coil. Mine was just a LITTLE out of spec, and it was blowing fuses & killing the engine. I was sure it was something else until it died on a long trip.

 

It seemed for a while that the coil fixed my problem. Went to a new OE coil, and it ran great for 2 months. Now I am back to a no start, and intermittent stalling when it does start. Everything checks out as per Haynes ignition wise, and the truck runs very strong except for the issue of it dying.

The only pattern I can find to the stall at this point is that it always occurs coming off idle (such as leaving a stop light) or at very low RPM (under 1200) could it be that I just need to adjust idle speed? It lopes steadily at about 650-700, slightly under spec IIRC.

Trouble started again after a long highway drive, and a light tow (~2000 lbs.) but I have a feeling it isn't related. Any help is always appreciated.

 

Have you ever checked the fuel pressure? Sears sells a gauge for ~$25 that will reach out the back of the hood to a wiper so you can see it while driving. Look in the EFI Fuel Pump album in my signature - there's a diagram of the fuel pump assembly that has a chart at the bottom, and shows how to force the fuel pump to run.

Also, check the red vacuum line on the FPR for gasoline, or even the odor.



There's no idle adjustment. The EEC handles that thru the IAC, but it has no effect when the throttle is NOT at the idle stop.

 

Hi
I do not respond very often, but when I do I am always wrong.
I have a 1995 f150 302 with about 360k, and about 10k ago,
I had a problem.
Get in start 1 to 2 min warmup, after 10 to 30min it would cut out.
I drive about 50 miles to work (1 hr).
The cut out was complete, if I did full a full pedal, it would run 30 sec
than recycle, wide open throtle (wot) is good.

Short story the o2 sensor was bad, Had oil on it.
Replaced the leaking head gaskets, and sensor.
Took about 300miles to start running with no cut outs again.
I asked here about the problem, and got no answer, I
also asked about the recovery time and got no answer.
This is just my story.

Chiltons for the 89 to 92 Mustang book, (if I rember, replace
every 5 years).

For my problem:
I had been told everything from , EGR,CAT CONVERTER, FUEL FILTER,
just bad replace it(the truck, worn out), (ford),
do not know get a new one, too old. got a 20k offer to "make it work".

In the old days (dig) you could pull a gas line or attach a timing
light and know almost everything.

By the way any one offer a general ballpark price
for replacing head gaskets 302 f150
or mustang, just a price concept, at 63 yrs old I now must pay for it.
Ford still cannot understand that a compression test or,
I found there is a test for the cooling system.

wrong100

 

I had similar symptoms for a brief period, and finally it died coming off of idle from a light one day.

I had fried an aftermarket ignition box a couple months earlier, and never put the two together. Since you mentioned coil problems you might have the same end problem.

After scratching my head and doing a lot of in depth trouble shooting, I decided to check my plug wires. As with you, they were good wires with no many miles on them. My primary wire to the distributor cap had HUGE resistance, and the truck promptly fired and ran fine after replacing it.

We had checked for spark before I got the truck back to my house, and it looked fine. But making a spark without pressure in the cylinder wouldn't be as hard on the wires. I'm fairly sure my box failure caused my problem, but since you've had coil problems it might be worth a quick check.

I just wish I had checked the little things first.