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Nov. 22, 2008 4:12 p.m. skruffy Dork

Thought this might be interesting on here since we're all into strange (sometimes even English) cars.

Friend of mine had a Audi 5000 Turbo Quattro that, amongst the many problems, wouldn't make boost while turning left. Even after replacing the entire engine harness and almost all of the vacuum lines (after an engine fire, not specifically for this problem), if you turned left you didn't get horsepressures.

My P5 will sometimes die while idling. You'll be sitting at a light and it's like you just turned off the key. Seems to be a common problem with FSDE engines. No way to replicate it and it only happens about twice a year. Mysterious.
Nov. 22, 2008 4:19 p.m. Feedyurhed Reader

Yup, that's a weird one.
Nov. 22, 2008 5:56 p.m. thatsnowinnebago Reader

I "fixed" the horn on my friend's suburban a while ago. It would honk whenever he turned left whether he wanted it to or not. I thought it was pretty funny.
Nov. 23, 2008 6:44 a.m. 924guy HalfDork

great topic! with my cars there are some very odd, but amazingly common weird ailments in the series. in the 924 turbo the fuel pump will sometimes activate when adjusting the power windows. in the 78, if the pos battery cable (has a couple of leads constructed into it, not just a straight cable) isnt well shielded, over time it will degrade and build resistance which in turn creates all sort of freakish issues, from simple rough running, to actually acting as a rev limiter, preventing them from running over 2500-3000 rpm.. and in any of them, if even one of the chasis grounds corrodes, it can casue all sorts of havoc and even engine cut out at speed, to less obvious issues like rough idle and a bouncy tach needle.. oh the joy... but the multimeter is a good gremlin hunter :)
Nov. 23, 2008 8:57 a.m. Grtechguy SuperDork

anything with lucas wiring?
Nov. 23, 2008 9:07 a.m. MadScientistMatt HalfDork

The previous owner of my Civic had "repaired" its suspension by putting brakes on one side that were nearly an inch smaller than the brakes on the opposite side.
Nov. 23, 2008 10:20 a.m. fornetti14 New Reader

Another haunted Audi... I had an Audi that would randomly cut all electrical function without notice. The fix? Every time it happened (weekly) I would have to slightly push on the main fuse box at the kick panel and it would come back to life. Even after a complete fuse panel replacement and inspection I couldn't make it stop LOL.
Nov. 23, 2008 10:37 a.m. Jensenman UltimaDork

My Nissan 4x4 had cruise etc, it did something really weird every once in a while. I'd go over a bump on the Interstate with the cruise on, the cruise would drop out and the red Brake light would come on. Reset the cruise and all was well. It was just plain wacky. I went over the wiring diagram, found a diode in the brake light and cruise circuit, aha! this must be it. Replaced the diode, damn thing did it AGAIN.

So one day when I was just cruising along, I bumped the dash near the fuseblock with my foot as I was getting comfy and the same thing happened. Hmmm. When I got a chance, I took the fuseblock cover off and drove it with the cruise and started tapping fuses. Sure enough, it happened. It turned out that a DPO had wired a trailer brake using one of those little doohickeys that wraps around a fuse 'leg' so you can tap power and it had spread the contacts just enough so the fuse could wiggle and break the circuit momentarily. I bent the contacts back into place and it never did it again.
Nov. 23, 2008 11:01 a.m. Strizzo Dork

driving home from school one day, my 93 ranger starts making a horrendous high frequency vibration. couldn't go more than about 55 or it felt like the whole truck was gonna come apart. get home, and driving slowly in the driveway i can hear clunk-clunk-clunk whicn then turns into the vibration at higher speeds. i crawl under the truck and for some reason the 4 bolts that attach the driveshaft yoke to the tailshaft had all backed out 1/2 turn, and was letting the whole thing flop around out of balance. considered pulling the rear driveshaft and running it on the front axle for the night (i had somewhere to be, and the rents wouldn't be home in time to take one of theirs) but i just tightened the bolts down and it held. i carried a 1/2 inch open end in the truck from then on, but never needed it.
Nov. 23, 2008 2:04 p.m. curtis73 Reader

Right now I have a tensioner pulley that about three times a year will lock up and throw the belt. If I ratchet it backwards and then forwards its fine for another 4 months. Its alsost like a needle bearing gets crooked every once in a while.

I had fun chasing down white smoke every time I turned left. It turned out to be a MC that leaked fluid into the booster. When I turned left it sloshed brake fluid into the vacuum line.

I have a 66 bonneville that in a left hand turn would make a really loud fast thumping on the floor. It turned out to be the left tranny crossmember mount. It had rusted on top where I couldn't see. When I turned, it would rise up and repeatedly smack the floor pan.
Nov. 23, 2008 3:53 p.m. Twin_Cam Dork

My Saturn sometimes forgets it has a clutch pedal, it will tell me upshift long after I've actually upshifted. This problem is accompanied by idling at 1800-2000 rpm rather than 850.
Nov. 23, 2008 5:09 p.m. foxtrapper SuperDork

Had a foxbody Mustang once years ago that had an awful rattle, every other bump. Drove me nuts for years. Sounded for all the world like a broken off fender support bracket on the bed of a pickup truck.

Finally, after crashing it again, I was taking the nose off and found a hidden support rod to the fender. It was off on the one end, and you could see how it would jam up on top of the tab, and then spring free. Repeat, repeat, repeat.
Nov. 23, 2008 5:50 p.m. alex Reader

Jensenman wrote: ...turned out that a DPO had wired a trailer brake using one of those little doohickeys that wraps around a fuse 'leg' so you can tap power and it had spread the contacts just enough...

I'm surprised I've never seen one of these 'power taps' on a fuse before. Sounds like the cousin of the nefarious 3M Scotchlock, which are terribly common with electrical motorcycle accessories. It's not a question of 'if,' but 'when' these evil little pieces of sh!t will fail. As a rule, we replace these when we're working on a bike even if they're not yet causing problems. Only a matter of time.

But, if I had a dime for every bike that I've seen wired with single strand household wiring and wire nuts...well, I'd have a bag of dimes heavy enough to beat somebody with who decides to wire their bike with wire nuts and single strand.
Nov. 23, 2008 6:49 p.m. CarKid1989 Reader

love power-taps for fuses. hahaha easy as pie
Nov. 23, 2008 8:14 p.m. Jensenman UltimaDork

alex wrote:

Jensenman wrote: ...turned out that a DPO had wired a trailer brake using one of those little doohickeys that wraps around a fuse 'leg' so you can tap power and it had spread the contacts just enough...

I'm surprised I've never seen one of these 'power taps' on a fuse before. Sounds like the cousin of the nefarious 3M Scotchlock, which are terribly common with electrical motorcycle accessories. It's not a question of 'if,' but 'when' these evil little pieces of sh!t will fail. As a rule, we replace these when we're working on a bike even if they're not yet causing problems. Only a matter of time.

But, if I had a dime for every bike that I've seen wired with single strand household wiring and wire nuts...well, I'd have a bag of dimes heavy enough to beat somebody with who decides to wire their bike with wire nuts and single strand.

This is what they look like and yes they are every bit as aggravating as the cheapie blue or red Scotchlok. About the Scotchlok: IMHO anything which cuts the wire's insulation and thus lets moisture in and then cuts strands in the wire is a really cheapo crappy design.
Nov. 23, 2008 8:22 p.m. daytonaer New Reader

My uncle had a 90's vintage audi sedan ( I only remember it was green). I asked him why he hated it and he said it was plagued with electrical problems. He had it on trip in the south and everything was going fine. The car would not have been more than a year old at the time. On the way home headed north it started to cool down, so he killed the A/C. The instant he touched the button the headlights died, at night on the highway at speed. He was able to get it home with the lights as long as the A/C was on a certain fan speed. Apparently it spooked him so much he sold it shortly after.
Nov. 24, 2008 8:12 a.m. porksboy HalfDork

My 96 Ranger 2.3 wouldn’t start one night when leaving work. Just a light click from the starter. Great I think, the battery crapped out. I push started it and drove to the parts store near home. The battery tested O.K. but when I turned the key it started right up, but… now the starter stays running but not engaged, even with the key out. WTF? Turns out the solenoid on the starter was loose and coming apart internally allowing the contacts to short together.
Nov. 24, 2008 2:36 p.m. GVX19 New Reader

this was a good one. this 2000 rav4 had no power when I took this snap shot.
Nov. 24, 2008 6:00 p.m. Jensenman UltimaDork

If I am reading this right, you have NO fuel trim, short or long. 99.6% engine load at 2000RPM? Hmmm.
Nov. 24, 2008 6:13 p.m. benzbaron New Reader

Driving the pickup on the highway I went over a bump and all the electricity cut out for one second, but went right back on so I drove on. Once I got home and tried to start it didn't. What was it? A loose battery terminal.

That scotchlock thing looks like trouble, glad my bike doesn't have any of them though might if I start adding stuff.
Nov. 24, 2008 6:42 p.m. amaff HalfDork

skruffy wrote: My P5 will sometimes die while idling. You'll be sitting at a light and it's like you just turned off the key. Seems to be a common problem with FSDE engines. No way to replicate it and it only happens about twice a year. Mysterious.

Chances are the EGR's all carboned up. The 'right' fix is to just replace the thing, a lot of people have had success pulling the EGR off and cleaning it. Me? I'm more of a fan of taking the intake off and squirting some Carb / Choke cleaner into the hole in the throttle body for the EGR, let it sit a few hours, then go for a drive. It's not a 'permanent' fix by any means (or at least not as permanent as the other 2 options are), but it's cheap, easy, and most of the time it works every time ;). Only had the opportunity to do it a couple times on the P5. It kinda became a "do it once a year and forget about it" kinda thing.
Nov. 24, 2008 8:33 p.m. aeronca65t Reader

When I was a kid, I had an old classic 850 Mini.

It used to crank over slowly, but would still start.

And for some reason, the throttle used to feel stiff when the engine was cranking.

One day, the throttle cable went up in smoke!

The block was getting it's ground through the throttle cable! (the regular ground cable was attached but loose).
Nov. 24, 2008 8:58 p.m. porksboy HalfDork

I played with a Lotus 7 that dumped engine oil and then wouldnt start. The engine was getting ground thru the brass oil pressure guage feed line.
Nov. 24, 2008 9:14 p.m. GVX19 New Reader

Jensenman wrote:

If I am reading this right, you have NO fuel trim, short or long. 99.6% engine load at 2000RPM? Hmmm.

Yes but if you look more closely. You will see that is not the biggest problem it has. The fuel trim is just telling you that, the ecm is happy runing at 14.7 afr.
Nov. 25, 2008 8:51 a.m. pigeon Reader

GVX19 wrote:

Jensenman wrote:

If I am reading this right, you have NO fuel trim, short or long. 99.6% engine load at 2000RPM? Hmmm.

Yes but if you look more closely. You will see that is not the biggest problem it has. The fuel trim is just telling you that, the ecm is happy runing at 14.7 afr.

Was that thing boosted? MAP is showing something like 4PSI over atmospheric, right?

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