WTF???, Turn head lights on, Car runs like crap! Options

[aircooledboy]

This my friends is why I am STRONGLY considering an alternative powerplant. (IMG:style_emoticons/default/confused24.gif)

Here is my deal: Drove the teener to the salt mine last thursday. (1.7 stock d-jet) Car's been running VERY well the last 3-4 weeks. Unexpectedly rains like hell at lunchtime. Have a meeting across town so I gotta drive. In the rain on the way, car begins to really hesitate and stumble, doesn't want to go over 4000 RPM, even small back fires 2-3x. After lunch, rain has stopped, no more backfiring, but bucks a little at lower RPM (ie 2000ish), still real tough to climb over 4500 on acceleration. Get it home, park it, figure it will be ok when dries out.

Didn't drive again until this morning (mon). Upon start, same deal w/ RPMs, but as the car warms up, less and less of an issue, by the time I get to office, seems to running good as usual. Coming home tonight: Starts fine, runs fine, but as i am leaving the parking deck, I turn on headlights, STARTS RUNNING LIKE SHIT again. I stop in the deck, pop the lid, and I see the headlights shining on the wall are damn near going out as the idle dives (battery 12 months old). Rev it up, lights come up. Turn headlights off, idle smooths out. It's still plenty light out, so I start the drive home. Every now and then, while driving home, I pop the lights up, engine suffers. Get out of the city, going about 70, pop lights up, can definitely feel engine running less smooth, but no loss of power. Pull into garage, turn headlights on, still affects the smoothness of the idle, but just a little. Then though, I notice that when I hit the brake lights, the headlights dim slightly?

help me, help me (IMG:style_emoticons/default/sad.gif)

Grounds?, alternator?, buy a V8?? Electrical issues are hands down my weak suit. Suggestions about where to start would be most appreciated.

Thanks,

Chris

[aircooledboy]

Seeing opera guy's post reminded me. Alternator light NOT on. Has come on intermitently in the past, but not recently. Lights and goes out properly on start up.

[seanery]

I'm no FI wiz, or even an electrical wiz, but it sounds like a short/ground issue.

[opera guy]

aircooledboy.. my car does that before the alternator light came on. mine is a bit different, and doesnt seem to be headlight (or electrical) related. motor would seriously buckle and knock as it tries to engage into first gear... now that i thought about it, i think my buckle problem is tranny related.

side note.. thx to seanery's pic, i did find my belt was off the alternator.

[Mark Henry]

I'm no FI wiz, or even an electrical wiz, but it sounds like a short/ground issue.

(IMG:style_emoticons/default/agree.gif)

Clean all you grounds!

Clean the battery terminals (both), where the strap bolts to the body, trans to body strap, all the wires on the starter, etc. On the straps sandpaper the contact point down to good clean metal.

Bad grounds can do some weird shit.

[aircooledboy]

Drove car to another city about 20 miles away this morning, and car ran great. I think you guys are right. Must be the grounds. Just what I need, another time consuming task on the teener. (IMG:style_emoticons/default/smash.gif)
Do V8's have ground issues?? (IMG:style_emoticons/default/w00t.gif)

Oh well. A well as the car ran this morning, I will be a little less whiney about the job. (IMG:style_emoticons/default/wub.gif)

[Mark Henry]

All older cars can have ground issues.

[BS Chairman]

Aircooledboy,
Try a different voltage regulator. I had this same thing the first of the driving season. Changed the regulator and the problem went away. Also the more things you run, lights, fan, wipers the less voltage you have going into the battery. So when the engine ask for more voltage it's hard pressed to keep up. Also make sure that all the grounds are clean to the body. Try this and we shouldn't have to come and pick you on your way to the Midwest Classic. (IMG:style_emoticons/default/rolleyes.gif)

[Mueller]

buy a digital volt meter and learn how to use it !!!!!!

if you can, spend a little more for a good quality one (I've got a couple of Flukes and I am happy with them)

[aircooledboy]

Aircooledboy,
Try a different voltage regulator. I had this same thing the first of the driving season. Changed the regulator and the problem went away. Also the more things you run, lights, fan, wipers the less voltage you have going into the battery. So when the engine ask for more voltage it's hard pressed to keep up. Also make sure that all the grounds are clean to the body. Try this and we shouldn't have to come and pick you on your way to the Midwest Classic.  :rolleyes:

As always,

Thanks for all the input guys. I will fool with these things as recomemnded. Except that reference to something called a vol-tage meter??? I think have such a device but it frightens me. I am not familiar with your modern ways.

Signed,

Frozen Caveman Gearhead (IMG:style_emoticons/default/laugh.gif) (IMG:style_emoticons/default/laugh.gif)

BTW, looks to be a pretty good chance those at the MWC will get to see a very exciting new addition to my little 914 collection. (IMG:style_emoticons/default/w00t.gif)

Shhhhhhhhhhhhh!

[Mark Henry]

I will fool with these things as recomemnded. Except that reference to something called a vol-tage meter??? I think have such a device but it frightens me. I am not familiar with your modern ways.

Don't know if your just kidding but...

The ohm part of the meter is simple enough, I use it daily for checking grounds and continuity.

On a digital meter set it to Ohm's and just look for a 0.0 (sometimes 0.2, etc) reading and on an analog for the needle to go to zero. You just have to touch the 2 probes together to see if it's working proper.
Simple as that.

[tat2dphreak]

I went through this with my old car, altenator was going out slowly... the alt light wasn't on... but it was coming, that's why the only time it was a problem was when the lights were on... everyone had great advice though... it could be ANY of the things mentioned!

[aircooledboy]

Mostly kidding on the volt meter. (IMG:style_emoticons/default/beer3.gif)

I have a couple actually, both of which appear to be capable of all kinds of shit I have no friggin' idea about. Hi-eva, I do know how to use the ohm / continuity function. I just really hate troubleshooting anything but the most basic electrical problem. (IMG:style_emoticons/default/ar15.gif)

I will clean my grounds and swap the regulator. I've got 3 or 4 laying around, and at least a couple of them look pretty clean. (IMG:style_emoticons/default/aktion035.gif)