VW Vortex - Volkswagen Forum banner
1 - 20 of 91 Posts

· Registered
Joined
·
34 Posts
Discussion Starter · #1 ·
Hey guys! I’m pretty new to the forum. I recently picked up my first Scirocco. After a few days, I was driving back to work from lunch and it started sputtering, lurching, and lost most of its power. I pulled over to see if it was smoking anywhere and then was able to lurch it in 1st and 2nd to a parking lot where she still resides lol. Originally when the problem happened, it would at least start up but would not run smooth ( almost sounded like a misfire). Me and my buddy spent the night trying to diagnose the issue. We checked to make sure fuel was getting to the engine, nothing out of the injectors. so we traced it back to the fuel distributor, took it apart and cleaned it. Now i have at least some fuel out of the distributor but it still won’t start. I’ve checked the battery, spark plugs (even replaced them just in case) cleaned off the distributor and distributor cap, and also cleaned off any corrosion on the wireset from the coil all the way to the distributor. She still will only turn over. Could it be a grounding issue? compression? something as simple as carbon build up in the cylinder ? Any help is appreciated !! Just need some outside opinions
 

· Registered
Joined
·
34 Posts
Discussion Starter · #3 ·
That car has two fuel pumps.
One by the passenger rear wheel, and another in the tank. I'd start there.
And if they need replacing, you replace both. And make sure that you purchase Bosch, not an aftermarket brand.
I’m still getting some fuel to the injectors now, so wouldn’t there be some sort of effort for combustion ? Or do you think it’s still a fuel pressure issue ?
 

· Registered
Joined
·
201 Posts
So that car is CIS driven.
If you have a vacuum leak it won't lift the CIS plate, so then you won't get fuel.
To really know, you'd need to do a bottle test. Hopefully you have a Bentley manual.
Basically your taking out the injectors and putting them in bottles.
Then you jump the pump system and lift the cis plate.
All bottles should fill evenly.
If your bottles fill. Then the next thing look for is a vacuum leak.
 

· Registered
Joined
·
51 Posts
the car needs T LEAST 55 psi of fuel pressure to run. some fuel wont do it. since it your first one i assume you dont have a fuel presure gauge. if you can get it started on starter fluid you have a fuel delivery issue. a common problom at this age is the in tank fuel pump or pickup that deterioates. the in tank pump serveves as a transfer pump to the high pressure pump that external. start there get gat to us
 

· Registered
Joined
·
34 Posts
Discussion Starter · #6 ·
So that car is CIS driven.
If you have a vacuum leak it won't lift the CIS plate, so then you won't get fuel.
To really know, you'd need to do a bottle test. Hopefully you have a Bentley manual.
Basically your taking out the injectors and putting them in bottles.
Then you jump the pump system and lift the cis plate.
All bottles should fill evenly.
If your bottles fill. Then the next thing look for is a vacuum leak.
Okay, fair enough. I’ve tried each individual injector in a bottle and they all got a fair amount of fuel, enough to create some sort of combustion. Where should I look for a vacuum leak ? the previous owner also suggested unplugging the cold start and trying to start it ? my main reasoning for looking for spark or electrical issues is because now when the engine turns over, it’s cranking slower than it usually would.
 

· Registered
Joined
·
34 Posts
Discussion Starter · #7 ·
the car needs T LEAST 55 psi of fuel pressure to run. some fuel wont do it. since it your first one i assume you dont have a fuel presure gauge. if you can get it started on starter fluid you have a fuel delivery issue. a common problom at this age is the in tank fuel pump or pickup that deterioates. the in tank pump serveves as a transfer pump to the high pressure pump that external. start there get gat to us
okay awesome, i’ll grab some starter fluid on my lunch and give it a try. When i tested the injectors every cylinder besides cylinder 2 had fuel. My train of thought was a blockage of some sort, but because these are manual injectors, fuel pressure does actually make more sense. especially because cylinder 3 & 4 had less fuel than cylinder one
 

· Registered
Joined
·
3,896 Posts
I’m still getting some fuel to the injectors now, so wouldn’t there be some sort of effort for combustion ? Or do you think it’s still a fuel pressure issue ?
The VDO transfer pump they used on '84 1/2 and up is crap.

Pierburg is the fuel transfer pump to get. I have a good used Pierburg, that I installed in my '88 16V Scirocco, and pulled it 6 months later, when I swapped the entire electrical system and engine in my 1979 Scirocco. I'd sell it for $30 plus shipping.

They also sell super cheap pumps on ebay, but I don't know how they hold up.

The transfer pump is the first to go, and it's really easy to replace. You pop the rear seat cushion, and the round coverplate. The trickiest part is getting the transfer pump mounting plate off. You can either make a jig, that fits the slots, or you can use 2 visegrips clamped onto the plate's lip, and you put a screwdriver through both visegrip's head and turn counterclockwise.
 

· Registered
Joined
·
34 Posts
Discussion Starter · #9 ·
The VDO transfer pump they used on '84 1/2 and up is crap.

Pierburg is the fuel transfer pump to get. I have a good used Pierburg, that I installed in my '88 16V Scirocco, and pulled it 6 months later, when I swapped the entire electrical system and engine in my 1979 Scirocco. I'd sell it for $30 plus shipping.

They also sell super cheap pumps on ebay, but I don't know how they hold up.

The transfer pump is the first to go, and it's really easy to replace. You pop the rear seat cushion, and the round coverplate. The trickiest part is getting the transfer pump mounting plate off. You can either make a jig, that fits the slots, or you can use 2 visegrips clamped onto the plate's lip, and you put a screwdriver through both visegrip's head and turn counterclockwise.
Awesome, thank you ! Let me try to figure out if i’m having fuel pressure problems first, and then if i am i’ll hit you up for the Fuel transfer pump.
 

· Registered
Joined
·
619 Posts
Get yourself and your buddy a copy of "Bosch Fuel Injection & Engine Management" by Probst. They're under $20 for used copies. It will explain the basics of how this voodoo under the hood works to make the engine run. Your 1.8L PL block isn't much different than the 1.8L HT block I swapped into my '80 Scirocco, along with the KE-Jetronic and knock sensing brain boxes from an '85 GTI. Probst explains all those systems.

The "bottle test" is a valid test, but you need to have 4 similarly sized bottles, and test the injectors simultaneously, for a given period of time, not individually.

I also know from experience that the Mk1 fuel tanks have a fine mesh basket screen in the bottom of the fuel tank. If you use a seal removal pick, you can fish the basket out of the bottom of the tank, via the fuel sender opening under the back seat and check the screen for debris. I once owned a car that had lived without a fuel cap for several months, as a result, there was rust on the top of the inside of the fuel tank that found its way into the fine mesh screen, clogging it up. It would run fine for awhile, and then sputter and die. Swapping cannister fuel filters wasn't enough. Finally swapped the tank to get rid of the rust on the ceiling inside the tank, but in the process I got good and pulling the back seat, the fuel tank sender, and popping that little basket filter out of the tank to blow it out with compressed air.
 

· Registered
Joined
·
9,418 Posts
DO NOT USE starter fluid. It could ignite and blow sh!t up. To use it, you have to open a path to the intake. Even if it doesn't blow anything up, it's not a carburetor. The fuel is provided by the pump and metered by Fuel Distributor and won't magically appear if you spray a flammable gas into the intake.

The intake duct was only used on the Scirocco 16V. If you blow it up you are going to be buying a replacement for whatever price the seller wants to charge.

Buy the correct Bentley. Start at the beginning.

I posted the steps in another thread and somebody still accused me of not being specific. I will try to find the thread later.

To Butcher's point, how did you clean the Fuel Distributor? They are precise fuel metering devices. You neeed to measure everything as you take it apart and it must be spotless. Every part has to be put back in the exact same spot it came from except screws. You can soak the parts in carburetor cleaner but you have to have a way to make sure they go back where they came from and have the same measurements as before. Either that or you need the Bosch lab equipment to make sure you can adjust it to the Bosch specifications.

My '88 Scirocco 16V was garaged in Bremerton from 1992 to 2013. It has old fuel not being started problems but will run. Just not dependably enough to drive anywhere I can't push it back.

I second the advice to get the Bosch Blue Book but you can't do without the Bentley
 

· Registered
Joined
·
9,418 Posts
A few things I just thought of. I don't know if they are Scirocco 16V specific.

The fuel pump relay has a fuse but it's not on the top of the fuel pump relay. It's in the fuse section of the Relay Plate (fuse box). The ignition system has a fuse also. Check those.

I counted the fuses wrong when my '88 was new. The ignition fuse I counted to was still good so I bought a new Relay Plate. When I was replacing it, I was swapping the fuses over after I had swapped the wires on the back over to the new fuse box. When I got to the ignition fuse, it was blown. I had been off by one fuse. I took the new Relay Plate back to the independent shop and had to pay a restocking fee. I should have kept it for the future but I needed the money.

One good thing is that the Fuel Distributor was used in several cars including the Ferrari 308 GTB and GTS QV (2 each because V8) and the Mercedes-Benz 190E 16V. Its Bosch part number is 0438101005. It should work right out of the box (assuming it's new or rebuilt) because a Scirocco 16V will start and run on the default settings.

Good luck.

-OE
 

· Registered
Joined
·
9,418 Posts
I’ve tried each individual injector in a bottle and they all got a fair amount of fuel, enough to create some sort of combustion. Where should I look for a vacuum leak ? the previous owner also suggested unplugging the cold start and trying to start it ? my main reasoning for looking for spark or electrical issues is because now when the engine turns over, it’s cranking slower than it usually would.
Check for cracks in the intake boot and any hoses that go to the intake or intake boot.

If it's cranking slowly, try charging or jumping the battery.

If all else fails, a diesel starter was a popular upgrade. (But that's for later after you get it running.)

I have mentioned this before but mine would refuse to crank in the TX heat after the engine warmed up but I never had a (cranking) problem after I moved it up to the PNW. It cranks just fine in UT also.

The previous owner may know something. If the Thermo Time Switch is cold, the Cold Start Valve will keep dumping fuel in the intake. The Thermo Time Switch has a timer and a bimetallic switch inside but that takes time.
 

· Registered
Joined
·
34 Posts
Discussion Starter · #17 ·
Define 'took it apart'. That could be the reason why it will never run again.
We took it apart after it decided to not start. but we just disassembled it and cleaned every part, leaving the film in place. after we cleaned it we started getting fuel out of the fuel distributor and to the injectors, which we hadn’t been able to do before
 

· Registered
Joined
·
34 Posts
Discussion Starter · #18 ·
Check for cracks in the intake boot and any hoses that go to the intake or intake boot.

If it's cranking slowly, try charging or jumping the battery.

If all else fails, a diesel starter was a popular upgrade. (But that's for later after you get it running.)

I have mentioned this before but mine would refuse to crank in the TX heat after the engine warmed up but I never had a (cranking) problem after I moved it up to the PNW. It cranks just fine in UT also.

The previous owner may know something. If the Thermo Time Switch is cold, the Cold Start Valve will keep dumping fuel in the intake. The Thermo Time Switch has a timer and a bimetallic switch inside but that takes time.
I also forgot to mention that I checked most, if not all, of the intake system. no issues or leaks. previous owner had put a duralast idle control valve on that kept the car from starting if it was plugged in. so for now the idle control valve is unplugged, i doubt that would cause this issue though. we also tried starting it on a jump to no avail. i haven’t checked the fuel pump relay but did try the ignition with one that was laying in the car, also to no avail
 
1 - 20 of 91 Posts
Top