Why does my 82 only go 30mph?

[mxracer170]

On Monday on the way home from work I couldn’t go over 30mph. She’s lost all power. Car starts great and idles great but has lost all power. I’m still getting about 40mpg.

I’ve tried running injector cleaner through it and that doesn’t seem to be helping.
I pulled out the fuel filter and it appears clean.

Could it be a stuck valve?

Any ideas?

[82vdub]

You pulled out the fuel filter and did you replace it with a new one? Do you have a clear fuel line going from the injector pump to the fuel filter? You may see bubbles in this line leading to a fuel issue. How does it start? You could have a slipped timing belt or something that caused the timing to change.

[mxracer170]

I did not replace the fuel filter with a new one but I think the previous owner did about 10K ago. Car starts great. The fuel line from the filter to the IP is solid fuel. Once and awhile I'll see a bubble but not to often. I'll start from a stop and the car will have no power, only goes like 10mph in first gear then all of asudded a little spurt of power then it goes away.

[v8volvo]

Definitely sounds like a fuel restriction issue. No smoke in all of this, I assume?

You may have gotten a bad batch of fuel. That could be causing the problem directly, or it could have plugged the filter up and now that is giving you the trouble. Fatmobile will tell you to put a vacuum gauge on your fuel line, and it's good advice. Somewhere something is preventing your engine from getting the fuel it needs.

[VW Jon]

Is your accelerator cable opening the throttle completely? Could it have slipped? Adjustment clip came off?

[Fatmobile]

That'd be my first guess.
Cable might not be pulling the arm all the way to the stop.
Usually takes 2 of me to test this,..
one to step on the peddle and one in the engine bay to see how far it moves.

[82vdub]

Usually takes 2 of me to test this,..

There's two of you????

[82vdub]

Even thought the previous owner changed the fuel filter 10k miles ago, are you 100% absolutely positive that he did change it, and are you sure that it's not plugged? I've defaulted to changing my fuel filters once a year no matter how many miles I put on the car. The water that sits in there (does anyone ever drain the water off theirs) and could get sucked into the motor isn't worth the cost of the filters, IMO.

If you inspect the throttle cable and it's ok and after you change the fuel filter and you still have the problem, rig up an aftermarket $1 fuel filter and separate fuel line directly to the IP and run it then. If the car runs great, you have a fuel issue somewhere between your new replaced fuel filter and the tank. If the car still runs the same, then you have an issue somewhere else. I still believe it's fuel related.

[v8volvo]

Is your accelerator cable opening the throttle completely? Could it have slipped? Adjustment clip came off?

Hadn't thought of this, it's a good possibility too though. This is on a Rabbit, right? On those there is a little bushing that sits in the top of the accelerator pedal; that can wear through and decrease how much action you can get on the cable. If the pedal seems to sit lower now than it did before you need to check that out, as well as the attachment at the pump.

Pump levers could also have slipped a few degrees if their retaining nuts were loose? Strange things can happen on these diesels that vibrate all day...

Sounds like it's definitely in the fuel or in the throttle linkage. Worst case it could be an internal problem in the pump, but those are pretty rare, and pretty much never come all of a sudden like your troubles did.

[hagar]

hagars diagnosis brass screen in tank No need to clean it before running a litre from a bottle to see how she runs.

hagar.

PS : all my ParoWax friends know what I am saying. EH ?

[82vdub]

all my ParoWax friends know what I am saying. EH ?

I've got a jar outside waiting for warm temps to start the melting process

[mxracer170]

I just got home from work and wanted to test the theory of the throttle cable not fully opening the IP. I put a battery on the pedal and sure enough even though I've been pressing the pedal all the way to the floor, like I have since I got the car, it was only opening the IP linkage at best halfway.

Now that I know what the problem is it shouldn't be to hard to figure out how to fix it. Is this a common thing on these cars?

Thanks for the help.

[tawney]

The little clip on the sheath right on the bracket on the injection pump might have fallen off, the sheath might have broken, and as mentioned before the rubber grommet can wear through or split. After 27 years or so, yes, it's common.

[Fatmobile]

Ahh yes, forgot to mention that if there aren't 2 of you; a battery can be placed on the peddle.
I've had it happen before,
along with the didn't tighten the idle screw lock nut,.. and eventually the car won't idle.

It doesn't happens often,..
but it's the easiest cure for the problem so first thing to check.
VW Jon gets the points for this one

Try to set it so the peddle hits the floor about the time it hits the stop,..
if you need to floor it and it hits the stop early, that can put alot of stress on the peddle bushing (V8volvo mentioned) and hook.
You could end up with no peddle if the hook straightens out.

[v8volvo]

Yep, common. And if you are able to see the fuel lever moving only half way, you know the pump levers are OK -- the problem lies in the cable mechanism, at one end or the other. Check where it hooks in at the top of the accelerator pedal, as mentioned before, and check that something hasn't come off on the engine side either.