Car (98 prelude, pretty stock h22a4) starts up fine, runs perfect then randomly does this:

-tach goes crazy(needle jumps around, sometimes drops to zero). weird thing is, somtimes the engine doesn't go with it, like im at zero rpm's for a split second but my engine is running fine, but usually the engine acts up with it.

-also ranomly, when i press on the gas pedal, i lose power instead, tach usually goes retarded at the same time.

-and once in a while, it'll stall while all this is happening.

-also, while im just cruising, my car will buck a lil as my rpms jump up and down a few hundred rpm's. again all these problems go away then come back who knows when.

i searched for people who had similar problems and most of the results point to a bad ignitor/coil or dizzy. seems right? i posted this problem last year, still havent got around to it.

 

I dont know how u have been driving with a car like that...

But do you have any CEL's?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by roller3804 &raquo;</TD></TR><TR><TD CLASS="quote">I dont know how u have been driving with a car like that...</TD></TR></TABLE>

word! sounds like a bad sensor somewhere, which should cause a CEL but not necessarily if the problem comes and goes. have your tried resetting the ECU? you should check all your vacuum lines, wire harnesses, and sensors to make sure that they are all hooked up right and working fine. when does the car do this? normal driving or when you push on it a little? going slow or fast? does it happen when the car is cold or hot, or both? also, check your spark plugs, wires, and dizzy for any abnormal color or wear. good luck to you!

 

It did it again last night. It happens anytime, normal driving or if pushing it, slow and fast(like on the freeway). Last night I was driving normal and this time it showed no warning signs, the engine just turned off and I didnt even realize it til I noticed I no longer had power steering. This happened when I was going about 10mph in a parking lot. Also, when I restarted the car, it just kept dying, it starts up fine but kept stalling again and again. It stalled about 5 times total and the only reason it didnt stall the 6th time is cuz I was pressing on the gas pedal to rev it up. After that, it ran fine. Again, sometimes theres just no warning signs, other times there is and I know its gonna stall(such as when the tach starts acting up)

To answer your question, it never stalled on me while the car is completely cold. It usually takes 5-7 mins upon initial start up for it to start acting up cuz by then it is warmed up but not hot. It also does it when its hot tho.

 

i know what you mean as far as the bucking goes... its happened to my car only twice while im driving it. and i couldnt pin point the cause but it hasnt done it since. im hoping it doesnt come back. didnt throw any codes.

bump for an answer

 

carbon build up in distributor cap? arching? clean that bitch foo

 

Could be the vehicle speed sensor (VSS). Just from what you are saying about the tach and speedo going crazy. if you have a CEL go to autozone and have them scan it.

Code I suspect you may get:

P0500--VSS

If you use the jumper wire method it will be 17.

Since it comes and goes, it could be a bad connection.

 

sounds crazy but i had an 00 ex civic do this and turned out to be alternator. i would go to an auto parts store and have them run a check on the alternator and battery.

 

only thing I can think of are:
- main relay
- faulty/intermittent grounding
check if the ground under the VTEC sloenoid is good.........also the one from the battery going to the front of the tranny

main relay probs will also have the car turn over but not start, u dont hear it click and the fuel pump doesnt prime the rails..........

good luck!

 

sounds like a bad igniter to me. same thing was happening to my car, bucking, random loss of power, engine would randomly die, etc.. changed out the ingiter and all was gravy...

notorious things that go bad on honda/acuras:

main relay
igniter
top of the radiator cracking
bad 3rd gear syncro

 

update? do you have a code?

 

Throttle Position Sensor

 

if the guages drop but the engine does not i still say VSS. maybe bad ground.

 

I'm having the same problems but my 93 b18b1 swapped civic sedan does it when I start it up or when driving randomly checked my ECU had some bernt spots so got a different one and the problems stayed the same some days it's fine others I can't even drive it

 

 

bouncing tach = bad ignitor