My Biagini Passo (Golf Mk1 engine) will not idle

Hello guys,

I've been reading the forum and found loads of useful information on here! But there is a problem I can't find a solution to…

I'm the owner of a Biagini Passo. For those who don't know what it is, it's a car made by an Italian company in the early 1990s, based on the VW Golf 1.8 Synchro mechanics (electronic injection). It was taken off the road a few years ago, since it was rusting through and was no longer decent to ride on the road. It was parked on a private property where it sat, occasionally turned on and moved from one spot to the next. Last time I tried turning it on a couple of years ago, it wouldn't start. I tried a few things, then gave up. I just hooked it to another car and towed it to another spot.

Early this year, I gave it another try. I found out that the pumps were not turning on (both the one in the tank and the one underneath the car), and the fuse controlling them had blown. Replacing the fuse would result in it blowing again. Once again, due to lack of time, I gave up.

Finally, a few weeks ago, I had some time to look at it again. I bypassed the fuel pumps power supply (now they're connected to +12V through a switch… not safe, I know, but it gets the job done at the moment) and the car finally started! It was actually running ok, all things considered.

However, the idle was rough at best. Sometimes, it would hover arounf the 1000rpm mark quite happily and smoothly, other times it would go down to 6-700, then up to 1500, then maybe drop down again and turn itself off. Recently, it turns on and turn off almost immediately, unless I keep the rpm up. It's not running as smooth either, and white smoke comes out of the exhaust (it doesn't seem to drink oil or coolant, but I use it way too little to be able to tell). I cleaned the throttle body (which wasn't that dirty to begin with) and examined the spark plugs, which are indeed sooty.

I guess something is off with the fuel system, but with me being no mechanic, I'm running out of ideas to try.

The car is not insured and I would not be able to bring it to a mechanic, unless I had it towed there and back. Plus, I really just need to use it in the property to move some tools around, so I'd be happy with it running ok: I don't need it to be perfect, and my finances at the moment require me to do all of the work myself.

The car will never set foot on public roads again… It's too far gone. I just want to use it occasionally, and give it some love so that it keeps on going until it eventually dies on me. At the moment, it's at 210k km. I'm planning a brake job, timing belt replacement and a few other things, but I won't start any of them until the motor runs ok.

Anyway, sorry about the long post, and thanks to anyone who can point me in the right direction!

I want to see this thing!!!!!

Sounds interesting to say the least.

sounds like the tick over isn't doing what it should, but as it's injection I'm lost, sorry.

I presume you're trying it on new fuel? is the filter clean and are the leads all ok?

Welcome to the club by the way  

Ian

borednow said

I want to see this thing!!!!!

Sounds interesting to say the least.

sounds like the tick over isn't doing what it should, but as it's injection I'm lost, sorry.

I presume you're trying it on new fuel? is the filter clean and are the leads all ok?

Welcome to the club by the way  

Ian

This is the car in question:
https://www.allcarindex.com/auto-car-model/Italy-Biagini-Passo/

It's not mine specifically, mine looks awful compared to those…

Anyhow, it's running on new fuel and the filter appears to be clean. Is there a way to make sure?

Thanks for the interest!

assuming its on the kjet fuel injection system, check the WUR and AAV wiring in the engine bay. the red/white wire on them both is also fed by the fuel pump fuse so if shorted out or if either of the units are faulty inside then it would cause it to blow straight away.

likewise check wiring to the fuel pumps as well

How old is the petrol in the car?
Petrol goes off after about a year, get some fresh petrol in the tank and see if that helps?

Rust in the fuel tank blocking the lift pump in the fuel tank?

First of all, thanks for the replies! I'd connected the power to the cable harness that feeds both pumps and anything else connected to them, so that wasn't the problem as far as I could tell! I had also put fresh petrol in the tank (there was none in there!).
Anyway, I made some progress! I realized that there was a leak in the plastic pipe that connects the fuel filter to the metal pipe that goes to the injectors: once turned on, fuel would get sprayed everywhere and there would be no pressure in the system. Once that was fixed, the car started working perfectly, idling at 1000 rpms!
Or so I thought… The secondary pump (the one underneath the car, not the one in the tank) started making more and more noise: it sounded as if a bee was trapped in the car… I thought the pump was defective. After a while, the car started sputtering and off it went.
So once again I went underneath the car, unplugged the pipe from the pump and tried turning it on (through the switch I installed). Instead of a solid jet of fuel, at first I just got a few little streams, then finally it started coming out as a solid jet. I reconnected everything and the car started working perfectly again and the pump wasn't making any more noises! So I thought the pump had just needed to be primed…
I was wrong. After a few minutes of use, I was back to the noisy pump and the car not working properly. Priming it again fixed the problem, but I haven't used it since and I'm sure it will go back to the same problem soon.
At this point, I'm guessing the pump in the tank isn't doing its job? Maybe there is rust in the tank as suggested? It almost seems as if the accumulation chamber connected to the secondary pump is almost empty until I unplug the pump, and only then it fills up. Is it supposed to be under high pressure?
As always, thanks to everyone who's taking an interest!

Have a look in the tank for rust, there is an inspection hole on top, if you remove the lift pump you will be able to have a good look in and check the filter on the end of the lift pump, the last thing you want is rust and dirt getting into the fuel system as it will start to cause problems further down the fuel system and then it starts to get expensive.

start here:
View topic: Fuel Tank cleaning *HowTo* clear that blockage - The Mk1 Golf Owners Club

the lifter pump has a filter on the end, plus can see in that thread you may have a filter in the feed end of the main pump.

for lifter pump check disconnect the feed line from it and put a pipe on it pointed into a jug. then get a 17, 18 or 100 relay and pop it into slot 2. turn on the ignition for 10 seconds, and the lifter pump should supply at least 300cc of fuel

borednow said

I want to see this thing!!!!!

you cant un-see it!   

Biagini Passo - Google Search

Ok… what is that…. it sort of looks like a Golf from the side… Hum…. not sure… some thing completely different and I can say that is the 1st time I've seen one of those.