Diagnose My Car Trouble

1987 Dodge Dakota Pickup Truck, 137,000 + change miles…

Last fall it develops this problem where it dies every time I take my foot off the gas pedal. Two days later the brakes go out completely.

Well, last fall I was so broke I was rolling pennies for Ramen noodles, so basically I just let the damn thing sit until I got it into the shop in mid-January. They “fix” it. Now, the brakes aren’t great, but they get the job done. And the truck sputters and shimmys and feels like it’s going to die every time I take my foot off the gas pedal, but it doesn’t.

About two weeks after I get it out of the shop, the brakes go bad again. I take it to my stepfather, and we bleed the air out of the lines. The breaks a great, for a couple of days; then they start going bad again.

Then one morning, guess what! It starts dying every time I take my foot off the gas pedal.

IFO think the two problems are definitely related.

Anybody care to venture a guess as two what the problem is?

FTR, it’s in the shop again right now.


I’m sure you’ll get some great info here (though not from me, I’m afraid!) But the above link is to a fairly informative MB geared towards auto problems & questions; lots of mechanics post on that board. You could try there, too.

First off, ye’ve got yerself a Dodge…

I just ran this by another guy here at work and we both agree that we don’t think they’re related. Sounds like your master cylinder. Your other problem could be with the ignition module. Does it happen more when the truck is hot, or all the time?

Ok, First off the hesitation and powerloss when you take your foot off the gas, most likely this is caused by a clogged fuel filter, easy to replace, not too expensive. Brakes on the other hand…

Since you’ve bled the lines and the problem still occurs there could be either a leak or a mafunctioning piston on one of the disc brakes. Also if you’ve got 137,000 miles on one set of Rotors that could cause a lot of problems on its own. Or one of your vacuum lines for your power assist brakes may have come lose or split causing an intermittent loss of power brakes.

In any Case the brakes are best left to a professional, where ever you do take it tell them everything that happens when you brake, it’s amazing what they can determine.

I don’t know what’s going on with your brakes… you could possibly need new brake pads. That’s just a guess but it worked for me when my brakes started going soft.

I had a similar problem (as for your truck sputtering when you take your foot off the gas pedal) and just got my car fixed last week. My car would only sputter and die after it was hot and I was thinking it was just a fuel filter but that wasn’t it. My problem was a lock up cylanoid in the tranny. They also put on a filter kit. It solved my problem and it only cost about $300.

Try edmunds.com they have a forum on every known car in the universe practically. One for each car so tons of guys there with the same car as yours & who know just what to do.

Based on the age of the car, Id say put in a new master cylinder & a carb if it has one.

I second Yardstick’s assesment.

The two problems are not related.

The stalling problem has to do with fuel getting to the engine. Most likely candidate is the fuel filters. Your car has either two or three of them. One in the tank itself which is more like a mesh. After years of use it can get clogged with debris. Leave it alone for now. Another filter is in-line (with the fuel line) near the tank. Change it but not before you change the fuel filter that is near the carb (inside your engine compartment). These last two (may only be one in your car) are cheap and easy to change and should be your first line of attack to fix the stalling problem.

Failing that, your carb my need a good cleaning. Your injectors may need a good cleaning as well. You can buy fuel additives to do that job. The carb may be so bad that it will require some more serious cleaning that will require a mechanic. You might want to replace and adjust the timing angle of your distributor cap and ignition rotor. They are cheap and worth replacing on a car that old.

Finally, you breaks are an entirely different problem. Once you get going (have your fuel problem fixed) you will need to stop. I would spend the money on the breaks before I spent money on the fuel problem. It’s more important to stop than to go IMHO. Sounds like you’ve got a crack/leak in your break line or power break cylinder. If you’ve bled the break lines and air got in again then a carefull inspection of these parts is in order. Have a qualified break specialist do this. It’s not something you want mess with or let an amateur try to fix.

Suppose you had a leaking master cylinder. I suppose that you have power brakes. Is it possible that brake fluid from the master cyl is getting sucked, by way of the power booster, into your intake manifold?

That would give you a crummy idle, since you’re trying to burn brake fluid, and your brake fluid level would go down, resulting in crummy brakes…

If the car has been braking evenly, even when braking poorly, I’d second the master cylinder idea. There also could be a vaccum problem with the brake booster–that could explain the dying when closing the throttle. If you don’t have enough vaccuum, you may not be backing off on the timing advance when you slow the motor down.

Are you losing brake fluid? Do you have to keep topping off the brake fluid reservoir that sits on top of the master cylinder? Does the pedal go all the way to the floor, or does braking just become ver, very difficult?

It is not unknown that a failed master cylinder combined with a failed diaphragm on the booster will allow brake fluid to be sucked out of the master cylinder.

If you have a carb, it may be time for a rebuild, but try using shooting some carb cleaner down its throat while revving the engine first. Also run a tank of gas with carb cleaner in it. Could be that the idle system is clogged. You could bump up the idle.

Probably the best idea was to take it to the shop again, and have them fix the brakes–that is one system on a car that you really, really want to work right! Glad that you did that.