Am i being cheated by the mechanic?

[vega_B]

Hey guys,

I just did an engine conversion on my mk2 gti, from 8v PB to 16v 9a. The reason why i did this conversion is to cure the old engine nightmare; high fuel and engine oil consumption (18 mpg city, 20 mpg highway) , bad compression, etc. The local mechanic told me that its better to swap in other engine instead of rebuilding the old one. After the conversion, much of the problem has been sorted out. There's only a couple of problem left (major):

1. High fuel consumption, getting 20mpg-ish

If I'm not mistaken, the mpg of a 9a engine should be around 30-35mpg, depending on driving habit (heavy/light foot). Since I'm a full time student, i can't afford to be paying the 'unnecessary' fuel consumption. So i addressed the problem to the mechanic and he told me that this is normal FC for 9a engine. What the heck? When i asked him about the condition of O2 sensor, he said mine doesn't have one. He also stated that some digifant 2 ecu doesn't use O2 sensor at all. Is this true? What can be done to sort out this problem? I really need get this problem fixed a.s.a.p.

2. Erratic idle

When the engine is cold it idles around 850-900, and when hot somewhere around 1000-1100. Besides that, the rpm drops quickly to 850-ish whenever I'm changing into gears. Sometimes if i don't maintain the rpm, the engine stalled. I've tried cleaning the Isv and TB, replaced all vacuum hoses, and checked for any vacuum leaks. It's very hard to drive around with this kind of idle especially in the traffic.

Here's some details of my ride:

- 1989 mk2 gti
- running on digifant 2
- 110k miles covered (8v), and 85k miles for 16v
- bad service history (previous owner)

Regarding the new engine, you'll be shocked when you see the weird head manifold job. There's a problem when using the old injectors, therefore the mechanic decided to use mk3 injectors. In order to use this injector, i had to use the head manifold taken from ABF engine. Everything seems to be okay, but due to its big butterfly the low speed drivability is on the crap side. Again he decided to modify it by cutting the original upper head manifold, and welded it to the ABF manifold runners. The idea is to use back the old TB. You guys might think that I've done something stupid here, but trust me there's no other options left. Here the local source for mk2 is terrible. That's why i had to proceed with his plans.

Please help me out guys.

regards,

[Crasher]

To change from an 8v PB to a 16v 9A is really stupid advice, I know as I have done it too many times and will never ever do it again. If you have an 8v Digifant, stay that way, if you want a 16v K-Jet, buy one ready made. The 9A is THE highest oil consumption engine VW have ever made in my experience and the fuel consumption will be much worse. A 9A has a lambda (O2) sensor, it is a critical component part of the KE-Motronic system so has he converted the car to basic K-Jet which is what I would do as the 9A’s KE Motronic is a truly awful system. Hang on, looking at that sytem it is not a 9A system, it is an ABF lower manifold and a KR or 9A upper manifold, that looks a complete mess-what has he done? I see a court case coming up!

[vega_B]

Crasher,

Yes i know, it's a complete mess. The car runs like *&%$ now. By the way, I'm from middle east, Malaysia to be exact. You might be wondering where on earth Malaysia is. Here, there's only a few workshops that are familiar with VW's. There's not much I can do right now except trying to figure out the best way to sort out the problem. Do you have any suggestion where i can start with?

Your help is very much appreciated sir.


regards,

[Crasher]

I do know a little about Malaysia, mostly about its history during the Second World War (as Malaya) and just after with the uprising etc, it’s a hobby of mine. VW were supposed to be getting involved with Proton but that has been shelved at the moment, it's a pity as it would have meant VW being involved with Lotus.

The only place to start with that job is to pull it all apart again and start from scratch with a sensible plan implemented by someone who knows what they are doing.

What is the base unit engine (block and head), a 9A or ABF?

[vega_B]

Well its nice to hear that someone knows about Malaysia. I was hoping for VW to be getting involved with Proton but sadly nothing happened, all due to politics. Sigh. I you happened to visit Malaysia, please do let me know. I want to meet the VW guru in person!

So far there's only a few mechanics that knows VW well. Less than five I think. Its a shame isn't it? I've spent thousands on the current mechanic, so before i move on to another workshop I would like him to at least supply me the necessary parts to fix the problem. Then I'll bring the car to someone else.

The base unit engine is 9A, except for the ABF manifold runners.

regards,

[Crasher]

I would think about converting the car the K-Jetronic with the full Golf 2 KR system that is if you can get your hands on the parts, which there are a lot of right from the fuel pump to the radiator. The other alternative is to go down the ABF Digifant route BUT the 9A does not have the position for the critical crankshaft speed sensor. A non VW route would be to use an aftermarket management system but these can prove extremely complicated. The KR route would be very easy to do and you could ask a breaker in the UK to package up all the parts required and mail them over to you. The UK would be the ideal source for KR parts as the car was very popular here and as some parts are specific right hand drive you would not have issues that you would buying the parts from mainland Europe such as the ECU bracket, wiring harness and exhaust down pipe.