FIXED:Wierd Idle problem on a 1999 acura 1.6el (d16y8)

[SEan]

It's an intermittant issue, but whats happening is: I come to a red light, after gearing down and coming to
a complete stop and the car completely in neutral, the rpm's will jump to 3000rpm without me touching the
gas pedal. They will stay there for about 1-3 minutes and then drop to 250rpm-600rpm and will stay idling at that rpm. Has only been happening for about 2-3 weeks. Operating temp and ambient temp don't seem to make a difference. Can happen after driving 5 minutes or 50 minutes. oBut once it starts, it happens almost every time. Any ideas??????

[Musclecar]

Check the voltage on your Throttle position sensor and make sure it is within spec.
Also, clean the IAC passage, could be all carboned up.

[SEan]

One thing I forgot to mention. I work for a dealership that offer's a fuel induction service through a company call BG Wagonmaster. While it was have a tune up, I decided to try running one of these services on my car. It basically includes a throttle body cleaning using a cleanser shot through while the vehicle is running, a cleanser through the fuel rail to clean injectors and a fuel additive. It's supposed to decarbonize everything and I was told by the rep it would be safe to use on my particular car. That was about 2 weeks before it started acting up. My thoughts are, they might be related. Maybe the cleansor was a little to harsh and damaged a sensor in the throttle body.

[SEan]

Does anyone have to specs for the tps voltage/resistance?????

[SEan]

The problem is constant now. Here is a new bit of info though. The rpm will only stay at 3000 rpm until the car is stopped now. While I'm driving, any speed, I'll push the clutch in and the rpm's will jump to 2000-3000rpm. If I push the clutch in while driving, it does this. If i hold the clutch in untill I come to a stop, it will continue to rev high until I am completely stopped. During all this I will not have touched the gas pedal after pushing in the clutch. However, when I push the clutch in while driving and the rpms do go up to 3000rpm, I'll rev the motor to say 4000rpm and release the gas pedal, the rpms return to normal, say around 750rpm. I happened to find an online Acura shop manual and I have followed to diagnostic flow chart for the iac and it's working. My question is, would a MAP sensor be causing this? I've also been told by honda tech's that it could also be my throttle cable sticking. That doesn't make sense to me only because it acts up only when the vehicle is moving. Someone please help, I'm losing it!!!!!!

[SEan]

I'm still waiting to hear back from honda techline, however, the MIL or CEL light came on today. When check, code p1336 come's up. Crankshaft Speed Fluctuation Sensor Intermittent interupion. Could this be the cause of my idle issue?

The TPS should be 0.48v if I remember correctly. Usually these problems are IACV related.

-Michael

[SEan]

Found the problem, FINALLY! With code's p1336 and p1337 both pointing to the crank fluctuation sensor, I had a look at the wiring. The tie strap holding the harness for the crank sensor let go, allowing the harness to rub up against the alternator belt causing it to remove the sheilding. After repairing the wire and resecuring everything, the car runs great!

[SEan]

Okay, so it's not completely fixed. It is 80% better than it was. Which leads me to believe
that there is still another underlying issue. I found an IACV to try, hopefully this weekend. I'm beggining to think that is the actual issue. As my car does not always idle high when warming up like it's supposed to... Anymore thought's??? Anyone???? PLEASE HELP!!!!

[SEan]

Well, thought the problem was gone. Actually, the car was fine for about 2 months. About a week ago, it started acting up again. No check engine light again. Brought it to a friend of mine at honda, he believes it to be either a wiring problem or a pcm problem. Unfortunately, no one in the shop had a pcm that would work on my car. Talking to another mechanic friend of mine, he is comparing it to a problem he used to experience with eagle talons. Basically, if a throttle body had been cleaned with a harsh chemical, it would destroy the air bypass in the throttle body itself. Basically described to me as wax type beeds which are controlled by engine coolant temp. As there are coolant line's running through my throttle body, he assume's it's the same. I don't however. All sensors seem to be reading okay. My honda tech said there were 2 sensors off. 1) tps was off by 2%, and 2) both oxygen sensor reading's on the scanner remained the same when the sensors were unplugged.

[SEan]

So after hours of electrical diag, and swapping out a few parts (ecu, iacv, etc...) I finally found out the tps doesn't seem to be working. When tested with an ohm metre, open circuit is present. So, what the heck, I tried replacing the throttle body as it's one peice with the tps. Sure enough, problem is gone. The car is back to it's old self... 7 months later, and it's FIXED!