bladesoxy

First of all, thanks for reading.

General info on the car:

'90 Integra RS w/170k +

Some background on the problem:

Randomly, car started to buck one day. This did not coincide with any recent maintenance, or tinkering that I've done. It mainly happens at light throttle (or cruising) the engine suddenly feels like a 60 hp tercel and the car bucks for a few seconds. This normally clears up after a few seconds or if i give it full throttle. The idle has always been a tad low, but was still smooth. No matter how far I turned the idle adjusting screw it would not move the idle. The idle became very rough around the same time the bucking started to happen. The idle drops slowly, to as low as ~150 rpms some times. There are times when I drive the car and the idle is fine and the bucking is non existent, but about 90% of the time that is not the case. More often then not it is when the car is warmed up. The car has a slight starting problem when cold. It needs to be cranked twice to start. This is not a problem when warm.

Recent Maintenance:

spark plugs ~6000 miles ago
new fuel filter
cleaned AICV
cleaned TB - idle rose slightly, idle adjusting screw still mostly ineffective
compression checked 6 months ago (200, 205, 190, 195, same wet and dry)
timing was adjusted before this started and car ran fine (hasn't been checked recently)
new main relay
car was seafoamed recently, no change in idle or performance

Upon searching I've found that there could be a lot of causes which is why I started a thread specific to my situation to see what the most likely problem is (TPS, Distributor rotor and cap, clogged injectors, etc...). Not to mention I'm sick of fixing things that aren't the problem.

Your help is much appreciated and if possible please include a brief description of how to perform the service you recommend and if possible an expected price on the parts if you know off hand.

THANKS A LOT

-Jason

EDIT: No CELs either.

THALADOR

i had this problem as well, i ran some Seafoam through my car, and it really smoothed my idle, and eliminated the bucking (car came out of storage), but i guess it didnt work for you

bladesoxy

Unfortunately not. Hopefully someone else will be able to chime in with some help.

omiehomie

i would have guessed something to do this your vac lines? have you checked those?

bladesoxy

When I cleaned out the TB and put it back on I missed a piece of the old gasket. The car had a vacuum leak that caused the idle to surge and make a whining sound. I sprayed carb cleaner on the lines looking for leaks and eventually found the leak at the TB itself, so I think it's safe to assume all the vacuum lines are in good shape.

Can you be more specific about which ones you think may be damaged and I'll make it a point to check them?

Sam92Teg

Sounds like an ignition problem, I would start with plug wires, then have your timing checked again. How old are your coil and ignitor?

ALMXDUPINTEGRA

Instead of cleaning the IACV replace it.

GSG2

check vacuum lines to MAP sensor and MAP sensor itself. had similar problems like you. sudden surge while cruising.

when the car is running in the garage I touched the MAP sensor lines and car died. map sensor had a broken tube for a vacuum line. fixed it and no problems anymore

hth

bladesoxy

Okay lots of good suggestions here.

First off I'm guessing that the coil and ignitor are original although I don't know for certain. I have never done mainenance on the ignition system so I wouldn't know what to look for there. I'm pretty sure it involves testing spark, correct? But any reason why it would be intermittent and not all the time? Same question for the wires. And what do you think is the problem with the wires? I'm pretty sure it wouldn't hurt to replace them since they are old anyways, but is there any thing I can check to see if they are working properly?

As far as replacing instead of cleaning the IACV; what makes you think that is the problem? I could understand it causing the rough idle, but would an IACV cause the car to buck?

The map sensor idea sounds very likely. I'll take a look at it today and report back my findings. Do you know how I should go about inspecting this?

BTW I have a HELMS Manual I can reference as well. But the troubleshooting in those books isn't always helpful.

Anyways thanks for the suggestions thus far.

-Jason

bladesoxy

Well I'm trying to readjust my timing right now and I can't seem to jump the service connector. It ended up being grey (oppose to blue like everyone says) and it was the only connector in the area that was unplugged. I put a paperclip in and the accessories still engaged. From what I've read the CEL should illuminate if the service connector is jumper regardless of whether or not you have a stored CEL code. Any ideas what I'm doing wrong? Thanks.


Modified by bladesoxy at 4:45 PM 5/15/2005

ALMXDUPINTEGRA

The IACV could cause the car to buck. When you first apply the throttle.

bladesoxy

Well I figured out that the service connector on a 2nd gen integ is grey and on the 90-91 integras it won't illuminate the cel when jumped. I got the timing set up nicely, checked out the rotor and cap on the distributor and everything looked good (took some pics that I'll post later). brushed off the ends of the spark plug wires with a wire brush. Nothing unusual around the map sensor, but I'm not quiet sure how to go about testing it. The timing alone made a noticeable difference. The bucking and idle are definately less frequent then before, but still does occur.

How would I know if I needed to replace the IACV? Last time I checked I remember them being quiet pricey so I would want to be sure before I replaced it.

Any other suggestions?

Thanks
-Jason


Modified by bladesoxy at 10:09 PM 5/17/2005

Greddy Dantegra

i've got the same problem on my 94 teg, and its happening right now, never got the chance to fix it. I got a friend whose a Acura Mechanic and he told me its the idle valve, it needs to be replace, if it doesnt stall out when the rpm drops close to 0 than dont worry about it.... you'll live... it happens to me probably like 2 days outta the week.... if your really worry about it, go get a new idle valve from acura dealer its gonna run you about $100 and up.... they sell it on ebay, here's the link

http://cgi.ebay.com/ebaymotors...=WD1V

Don't know if it will solve the problem, i'm about to order one myself, but if it does please let me know =P thank you.

spoolin gsr

u said that the timing was not checked since... first i would check that .... its could be that ur car is retarded too much and that causes lack of power and starting problems ....

bladesoxy

If you look at my previous post I took care of the timing this weekend and it did make a noticeable difference.

The ebay link is to a FIV.

I would still like to know how you check to see if an IACV has gone bad.


Modified by bladesoxy at 4:00 PM 5/18/2005

bladesoxy

^^^

bladesoxy

Here's the pics:









I have all weekend to work on this guys so please help me out with some info.

Thanks
-Jason

bladesoxy

Measured the resistance between all the plug wires and all are well within spec. Measured resistance at the coil between the positive and negative terminals and it fluctuated out of spec, and would settle in spec and out of spec (spec is 0.6-0.8 ohms). Is this a clear enough sign that the coil needs to be replaced? Also measured resistance between the positive terminal and the secondary winding resistance and it came up barely within spec (spec is 9,xxx - 14,640 ohms, my measurement was 14,3xx ohms). Both these readings were done while the engine hadn't completely cooled so I am going to remeasure the readings once the engine completely cools off.

BUMP FOR SOME HELP!

bladesoxy

I've had someone say they had the exact same problem and it was the O2 sensor. I'm gonna give that a try next weekend.

bladesoxy

Looks like it was the O2 sensor. Replaced it with a bosch and haven't had a problem since. Thanks to those that attempted to help.

-Jason

ChrisTApher05

I havent heard anyone mention their igniter yet, i had a very rough idle and replace the rotor, cap, ignition wires, checked vacuum lines, sensors,
replaced spark plugs etc, but once after i got a new igniter it stoped MY rough idle and very rough accleration at low speeds and high.
Hope that helps ya out in some way, give it a try