I just bought a 88 B2 with only 89,000 miles (confirmed with carfax). Drove it from San Francisco to Salt Lake City and it ran perfectly until the last few miles. I started up one of the canyons outside Salt Lake City and the engine quit. I had it towed to a Ford dealer. They replaced the in tank fuel pump and fuel filter. The car runs now but when driving up the canyon and around Salt Lake periodically the car goes through periods of loosing power then as if a switch is turned the car runs as it should. Then this cycle will start up again a short time after, loss of power then normal. The loss of power is more dramatic the higher up the canyon. If I hold the throttle to the floor it seems to run better. If I pull the car to the side of the road during the rough running time a few moments will pass and then like a switch is thrown the idle smooths out to normal. Salt Lake is about 4,600 the canyon I have been driving up goes to 9,600 in about 6 miles. Any suggestions will be greatly appreciated. Steve

 

Check the air filter ..make sure it's clean. Then what octane gas are you using?
I was just out in Moab, UT a month ago. We rented 2007 Jeep Rubicons..Climbing the mountains into Arches and Canyonlands the jeeps would loose power and could hear them start rattling.. Pulled over and pulled the air filters on all 3 jeeps and they were loaded with dust..at 3000miles on them. Took them out and continued the drive into the the park to Hells Revenge where we put the filters back in after beating the dust out. They ran good after removing the dust packed filters. Not much you can do about the gas since they use cheap crap in them.

 

Have you tried pulling codes from the computer? Checked fuel pressure? Checked the condition of spark plugs, filters, and other tune up items?

I live in Ut county, and my little BII (when I had it) had no trouble running up and down these mountains.

 

A bad TFI module will sometimes not even throw a code and will act like you have described. Or usually it throws a ton of codes.

Here is a quick test for your MAP sensor, which might be the problem. When it starts to lose power, pull to the side and shut it off. Let it sit for a few minutes, then try restarting the car. As I understand the Ford system, it recalibrates when off. Changing elevation of 1,000+ feet might be causing problems along with

Bad O2 sensor. No real way to determine this is bad without an expensive scanner. Easier to replace. Fairly easy to get at on a 88 BII.

You could have your MAP sensor tested or test it yourself with a very good DVM.

What you describe also sounds like the low pressure fuel pump failing while climbing the grade. Since that has been replaced already and now knowing that the low pressure regulator is in the cannister housing, I would look at replacing that.

The big question is, does any of this stuff happen while coming down from the 4600 feet? If not, that would certainly narrow the problem down (after testing the MAP).

 

I received this by private message, but, I am going to post it here for others to reply to.

> As a stab in the dark the TFI was replaced when
> I took it back to the Ford dealership.

It should have been $30-$40 for the part and .3 hours to change it, though up to an hour would be okay if they had to remove the distributor. You should not have to on a 1988. I replaced mine just leaning in over the fender.


How much did they charge? I would hope they didn't use a $180 Ford OEM replacement.

When I encounter unknown problems, first I check the grounds, then I change the TFI with a known good one. Most dealerships will have a known good one around for testing. If not, it is still the best procedure, imho.

When they changed the fuel filter, they might have tried to change the filter in the cannister (should not be one in a 1988) and damaged the cannister/pressure regulator. On one of my own vehicles, I had to put it on the lift, take the cannister out, put it in a vise, have one mechanic hold it with water pump plyers while I turned the top with another set. It was that hard to open and we are not small guys! I did damage the cannister a bit.

Until someone posted here, I never knew the pressure regulator was in the bottom 1/2. I can see someone damaging it or putting a filter in there and not putting it in correctly because sometimes you get O-rings that are not the right size or filters that are not the right size. Example: Someone gave me a filter once that was for the filter on the fuel pump for an older Ford instead of the correct cannister one. Luckily I knew the diffeence and didn't jam it in there.

Maybe you should ask if they changed both filters. It may be possible there is a dirty filter in the cannister if they did not change it or the wrong O ring/filter was used if they did.

> What confuses me is why if I run the car up the hill full throttle as much as I
> can the problem seems to disapear.

Besides using almost all the fuel available and not returning any to the tank, at WOT the computer ignores many sensors and just basically dumps as much gas as it can into the engine with timing advance.

> The car is still at the dealership and I am out about $1500 and the car
> does not run right.

Okay ... now that has my stomach a bit queasy. For $1500 you could have bought a primo 4x4, not to mention replaced every sensor in the vehicle, both fuel pumps, and had change left over from the labor.

How about posting copies of the repair orders?

> The same symptoms occur going down hill. Step on the throttle and the engine
> run rough then all of a sudden it runs well for a period then bad again.

Automatic or manual? This might be a bad torque converter/transmission slipping. When you pull it to the side of the road, you are cooling it off. Be nice to eliminate that as a possible problem.

Thee might be more then one problem with the car.

> If you have any other suggestions please pass them on to me. Steve

I could post additional thoughts about charging someone $1500 to fix a 20 year old vehicle, which is about what the vehicle is worth, and not fixing the problem, but, I doubt you would want to pass it on.

Let us see the repair orders, I want to see how they got up to $1500.

 

These prices are from Advance Auto for the various sensors

$53 MAP sensor easy to change .3 at the most
$19 coolant sensor easy to change .3-.6 depending on belts
$30 TPS sensor easy to change - to set up and road test 1.0 hour
$45 O2 sensor easy to hard - depends on rust and fragile connectors 1 to 3 hours.
$30 ABS wheel sensor easy .5

$50 knock sensor easy - but messy - one hour - it is right there, but, you have to fish the harness out from the top to disconnect it and you get covered in grease on a leaker.

$37 TFI module
$99 reman distributor with module (pickup) - med - 1.0-2 hour
--------
$363 in parts if you guessed and replaced everything

Throw in another $150 for both fuel pumps and filter.

Really - $1500 for guess work? For $1500 I would have expected every component except the CPU replaced with change left over. That is what I think.

The only item (if I was fixing the customer's care) I would have bought from Ford would have been the MAP sensor to make sure it was calibrated correctly out of the box. (Maybe even the 02) I still would have tested the MAP (most Ford dealers should still have the machine) before I installed it.

 

If it is ignition, it usually will not clear up when you "hold the throttle to the floor."


https://www.ford-trucks.com/forums/6...-extended.html

 

I agree that it most likely a fuel/mixture issue. I understand that the MAP sensor will recalibrate when the throttle is to the floor. Do you know this to be true?

 

I will look it up on my CD and see if it is mentioned.

 

My friend had a similar problem while he was in college. Hopefully you're in a better spot than him. Good luck

JD
Ford Engine Locator

 

The only good thing is that the car is at at Ford dealership. I am surprised that some mechanic on their staff did not know how to fix the problem.