I've replaced the whole set of injectors with new Bosch units about 50k ago. I've since had to replace one, maybe two individual injectors. The rough idle right now isn't as bad as it has been before when one injector went bad, but definitely rough, and intermittent. You'll be sitting at a light, it's idling perfectly, then all of a sudden it gets rough and stays that way. I have replaced my MAF (with a used one- no change).

Any other ideas?

Thanks.

 

Checked your hoses plugs wires.

 

maybe you should have replaced all of your injectors and maybe have gotten a brand new MAF just my .02

 

The first time around I DID replace all my injectors. After less than 50k, I'm not wild about replacing ALL the injectors again. I've heard that the injection system on the VG30E is a POS at best, but less than 50k out of a full set of new injectors? That's ridiculous. And $300 for a new MAF for a $1,500 car (even though it's a NICE car), doesn't make sense right now. If I was POSITIVE that the MAF would fix it, I'd do it in a minute. But until I'm sure what the prob is (especially when 2 shops and 1 dealer have troubleshot the thing and come up empty), I'm not dropping that kind of $$$ on it.

I will throw a set of wires on it though. I think I have a set I haven't installed.

 

I assume you tested the injectors instead of just assuming they are still good?

I would replace all the small hoses. They are usually at under a dollar per foot. The rubber hardens with age and can crack easily, so on a car this old its a good bit of maintenance.

May also want to replace your spark plugs and fuel filter for good measure.

 

Is testing the injectors something the average idiot (me) can do oneself? Do they have to be pulled, or is it a voltage or resistance-type check while installed?

 

You just need a voltmeter. Take off the harness from the injector and check the resistance across the connectors of each injector. On the VE its supposed to be 14 Ohms (or 12? Cant remember for sure), not sure about the VG but probably something similar.

If you measure no resistance or infinite resistance then its busted. A high value will mean that it works but poorly because it cant open all the way.

 

ive had rough idle (while in drive) for 4 years...... ...sorta got used to it....

 

Also check your injector connectors. Ive had a rough idle in my 240 for as long as Ive owned it and I just took 2 seconds to wiggle the #2 cyl and it ran so much smoother....

~Alex

 

VERY INTERESTING

 

One of my 85s had an issue where two cylinders were dead, if you wiggled the injector harness, they would temporarily come alive. Sprayed the connectors down with Electro-motive electrical cleaner and fixed it for good. A good idea on all the electrical connections when a car gets toward 20 yrs +.

 

I did the same but I used a grease. If you don't in a few more years you'll have that corrosion again, you should get some di-electric grease. It prevents the corrosion buildup forming again.

~Alex

 

check ur vaccum hoses (if they are hard and cracked, replace) and clean ur MAF (and the connection to it) with electronic cleaner. everything will cost less than $15 bucks

 

Thanks for the input. I'm going to give these suggestions a shot...

 

True. It was a temporary (read: GF wrecked it less than two weeks later) car, but I have that on th e "To-do" list on the new one. Die-electric grease FTW.