Let me start by saying that I love my silly old Rabbit. Presently though I am irritated and confused by its new quirk. When starting it spins with out turning over. It sounds to me like it is not getting fuel. It also tends to backfire (or something else that causes a small amount of smoke). It does inevitably start and once it is running it seems fine. It got a full tuneup this spring, I have checked the fuel pump and replaced the fuel regulator. The problem persists and I am running out of ideas. My present theory is that it has something to do with the ghost that lives in the wiring that recently made half of my instrument cluster dead, but that could and just be its own problem. Anyway, if you have any thoughts or information please let me know.
With older cars like this, are you sure the compression is still good? Weak compression can make it hard to start older cars. Also, weak fuel pumps can make it difficult to start. If the fuel pump requires extra time to get the pressure built up, it will definitely make it hard to start. One trick to determine if the pump is an issue is to turn the ignition on for 2 seconds, but don’t try to start the engine. Turn off the ignition, and wait a minute or two. Then, try to start it. If the engine starts right up, the fuel pump is getting weak or the check valve in the pump is bad, and letting residual fuel pressure leak down.
How many miles on this car? Does it use the old mechanical fuel injection or is it carbureted?
How many miles on the clock?
There’s a number of ways this could go as this is a CIS injected car but not enough info is known.
Just to throw a couple of things out to bet the ball rolling I might state:
How did you check the fuel pump? This requires a specialized pressure tester as these pumps run at far greater pressure (5 Bar or better) than normal FI pumps and the method for checking pressure is different.
The backfiring could (but not definitely) be caused by a worn distributor shaft which can also cause the engine to be difficult or impossible to start. It’s also not a rare problem.
CIS is also very cantankerous about vacuum leaks as that system will not tolerate any mild or severe leak at all. Even a minor leak can make them go stupid.
There some issues with the fuse block and pump wiring on these cars but I’ll withold getting into that for the time being due to length of the post and lack of info.
I believe, during this time period, some carbureted versions of this engine were produced…The REAL econo-models had carbs…
If it is FI, I wonder whether the lines are getting primed properly on start up.
Try this: bring the key to the position right before the start position a couple of times. You’ll hear a whirring noise coming from the tank area that lasts about a second. it basically pumps fuel up to the engine and brings it up to pressure so it can start.
Do that a couple of times and see if it likes to start after that.
It could be that the lines aren’t primed. Starting the car takes quite a bit of current that may starve the fuel pump so it doesn’t get a chance to bring the fuel pressure up to a point where it can run. The backfiring kinda supports the lack of fuel theory.
It could point to the fuel pump being a problem.
Edit: Oops - just noticed BustedKnuckes is heading in the same direction. Didn’t mean to dupe that advice.
From 1977 all Rabbits up through the upper mid 80s were CIS injected in one form or the other. Only the first 2 model years (75 and 76) were carbureted. The same held true for the Dashers and so on.
If this is a fuel problem not related to the wiring then the first step on a CIS car (and it’s a MUST) is having the special pressure tester, the pressure charts, and the understanding of how to properly run the tests and determine if the system pressures, cold control pressure, warm control pressure, and so on are correct.
The control pressure regulator (a.k.a. warm up regulator) is always suspect.
The 1982 VW Rabbit gasoline engine has a single barrel carburetor…72hp.
Thank you all for your input. I will do my best to address all that has been said or asked.
BustedKnuckles, I checked the fuel pump by replacing it with a new one, when the problem was still present I swapped it back (because if you could not tell by the 1982 Rabbit, I am dirt poor). I will certainly try your fuel pump check tomorrow morning though.
Caddyman & JosephEMeehan, 222,XXX miles on the clock but the motor was supposedly replaced shortly before I purchased it, not that that means much of anything (it is not original to the car any case). It has the mechanical fuel injection system (the CIS that OK4450 mentions).
OK4450, As mentioned above I checked the pump by replacing it and then swapping it back. I will look into this distributor shaft of which you speak as it is something I had not considered. And as for vacuum leaks I will double check but I did not find anything obvious in my time staring at and poking under the hood. The wiring is something I have my own concerns in regards to. Presently half if my instrument cluster is dead, the tachometer, fuel and temp gauge as well as the oil, turn signal and O2 lights. That problem was intermittent for a number of months and I figured out that if I fidgeted with the heater fan It would generally wake up, unfortunately now it is just dead.
RemcoW, I have tried priming it a few times before starting and all that seems to do is make it more likely to backfire. I even cracked the fuel line just after the filter and turned the key to on just to make sure it was pumping, and it sprayed gas for a second or two and then stopped. I would have thought that because the line was cracked it would pump continuously when it could not pressurize the system but I could and probably am mistaken.
Again, thank you all for offering advise and insight (and reading through a foolishly long post). I hope that I answered and explained things adequately and if not please let me know along with where you think I should go next.
One area that has been weak in this era of Rabbit is the fuse block wiring which is woefully undersized for the current load. The pumps draws a lot of amperage, even new, and much more as the pump wears, etc.
There’s a workaround if the fuse block has suffered any connector burning. Do this. Drop the flexible knee panel under the steering column. Remove the 1 Phillips screw holding the fuse block in place. Lift the block up slightly to raise it off of it’s supports and gently lower it a bit.
On the rear of the fuse block you will see a line of various colored wire connectors plugged into the block.
My memory is hazy on this due to so many years since I’ve done one of these but the connector on the outside end of the fuse block should be white in color. Look at the outside edge of that connector and note if you see any melted plastic or the white color replaced by brown or black burn marks.
If so, that could be the cause of no fuel pump operation and there’s a way of getting around this without replacing the fuse block. I’ll hold off on the how-to on that until it’s known that is possibly the cause.
I will also look into the fuse block as a potential cause today.