1.8L 16V tune-up - now runs worse

I just replaced the plugs, wires, cap, and rotor on my 88 Scirocco

16V. It was running reasonably well before - probably 90% power, with a little bit of hesitation on heavy acceleration. Now, the car has about 20% power. It will crank okay, but has a rough idle and alot of unburned gas coming out of the exhaust. It will rev (slowly) with the clutch disengaged, but barely has enough power to move the car when in gear. If I stomp the gas it hesitates really badly, threatens to stall, then will rev if it's not in gear. The idle is so rough it shakes the whole car.

Details - when I first cranked it after changing the parts, I forgot to reconnect the hall sender connector to the distributor. I disconnected it to clean it up. The car wouldn't crank at all without it connected. Also, there was a fair amount of oil in the distributor cap fouling the contacts. However, the car was running fairly well even with the oil fouling. About a week ago while messing around under hood, I inspected the knock sensor lead wire and the insulation disintegrated in my hand. It is still wrapped with an internal plastic wrap, just not the outer black rubber insulation. I looked at the knock sensor and the hard plastic insulator around the sensor itself has also disintegrated. The car has been sitting for about 3 years; this tune-up was to be the beginning of a restoration to start driving it again.

Theories - cranking without the hall sender or a disintegrating knock sensor has put the ignition control unit into "limp-home mode". Archived messages I've read point to bad knock sensors causing limp-home mode, but it was running fine before I changed the ignition parts. Another theory is that cleaning up the distributor around the rotor and hall trigger wheel damaged some oil-soaked internals.

I've checked and triple checked all of the plug wire connections, timing order, coil wire connection, etc. I've tried going back to the old plugs, wires, and cap, but it hasn't solved the problem. I couldn't put the old rotor back on because the new one is glued on too solidly. All of the new parts are genuine Bosch, and I'm using F6DTC tri-electrode plugs. I can't figure out what I did to make it run so poorly. I know that I probably need a new distributor because of the oil leak, and definitely a new knock sensor, but the car was running okay with the old ones. I don't want to throw $300 at the problem just to have it still running bad. So - anyone have any ideas before I order a new distributor?

Thanks Justin

Reply to
Justin
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you have your wires in the wrong order.

Reply to
Eduardo Kaftanski

Yes it would... you can easily reverse wires 2 and 3 and if would do exactly as you describe...

Reply to
Eduardo Kaftanski

If you didn't do 1 wire at a time then you got them mixed up. Remove the cap and look for a small slash on the dist housing which is #1 wire/cylinder.

Reply to
Woodchuck

Justin,

Having the wires in the wrong order was the 1st thing that jumped to mind. I'm with the other guys on this one.

TBerk did it on my old Ghia.

Reply to
T Berk

Maybe the O2 sensor died during the tune-up? ;) I'll 3rd or 4th the order of the wires (but humour me and unplug the O2 sensor, if not to introduce another variable).

Reply to
Darryl

Stupid Bentley. It says 1-3-4-2 clockwise, which is actually how I put them on. I wrote in an earlier post that I did it CCW, which is what I read in old archived messages. I was thinking that CCW was correct put actually did it according to the Bentley - which is only correct for the 8V, which it doesn't mention of course. I swapped 2 and 3 and it runs beautifully. Now I just have to put all of the new parts back on. Grrr. Thanks guys. I was certain that it wouldn't crank if the firing order was wrong, so dismissed that. I won't be buying a new distributor now!

Justin

Reply to
Justin

Wires or a defective cap/rotor.

I had a bad cap right out of the box that would intermittently cause the car to hesitate to the point if you pressed down slowly on the accelerator when it started to stumble you could press all the way to the floor and then the car would die.

Happened about twice a week.

I exchanged the cap and it fixed it although I could not see a thing wrong with the original and it was installed correctly.

This was not on a VW but just posted to illustrate that parts can be defective even if new.

psycho

Reply to
psycho_pastrami

This reminds me--once I removed my cap to clean the contacts and didn't notice untill the car was running rough that it had (somehow) developed a hairline crack.

Reply to
Darryl

I suspect that was the problem, but I didn't see any carbon tracks or anything like that but I think that was the cause.

psycho

Reply to
psycho_pastrami

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