i got a 1991 honda civic hb si......this just started to happen...when i'm in gear driveing...some times it lose power n jurks a little....likes he power truns on n off...wat should i do?...

 

(my bad..he>>>>the* power)

 

when's the last time you had a tune-up?

 

91 huh?

ignitor if it's electrical

filter, or pump if it's fuel.

 

If the jerking on off **** is happening when you are just slightly on the gas then you may have to play with your TPS.

 

wats tps?

 

It's the (T)hrottle (P)osition (S)ensor. Modern fuel injected cars have what's called fuel cut-off on deceleration. This occurs when the throttle body is closed(you let off the gas) and rpms is say greater than 1,200 rpms.

So if your TPS is off it may read that it is closed when it's not and you'll get fuel cut-off until rpms are below say 1,200 rpm and then fuel is turned back on to have the engine idle. I lived with this situation for about six months with my car bucking like a horse and I wanted to shoot it like a horse.

 

I've had the same problem recently with my 1990 Honda Civic and this site was a HUGE help......I was told to check the 4 wires that connect to the ignitor, make sure they are all snug. If one is loose or disconnected that is most likely your problem. I did this, and low and behold, I had a very very loose connector, I could have looked at it and it would have fallen off......Might want to check distributor cap for cracks also....

 

hey Rocket... I have been getting an IACV cel code recently. When the cel INITIALLY comes on... the idles jump to 2000 and bob back and forth quickly between 2000 and 2200. After driving it around like that for a while, the car just idles kinda high when rolling to a stop (in neutral or foot on clutch) or if I revv it, it goes up like normal, then it drops, then bounces up to 1500ish then slowly settles back to normal. And if I reset the ECU and the CEL is gone, it does the same thing I described in the previous sentence. My question is this... could this be from a bad TPS? I once had the TPS tapped for my Zex kit, but I've taken it off since november 01, and the idle problems started in january. I checked to see that the wire wasn't hacked up from the wire tap and it seemed fine to me. Also, I checked the voltage on the TPS and it's 0.52-4.58... is that correct? Please help me also.

EDIT: oh yah... when the cel initially comes on... it's hard as hell to drive and at low rpms the car shudders like hell also.


[Modified by CivicRyda2k, 9:33 AM 5/11/2002]

 

CivicRyda2k,


I'll get back to you on this. I am going to check my manual re the TPS values.

 

Here you go CivicRyda2K.

Your TPS should be fine. Your IAC may be stuck open. When your idle jumps to 2000 rpms unplug the connector and see if your rpms go down to 1000 rpms. If it does then your IAC valve is okay. If it doesn't the replace the IAC valve.

The reason why you have the shuddering is that your idle is too high and the ecu thinks it should be in decleration mode and cuts off the fuel at rpms greater than say 1200 rpms and your throttle position is nearly closed.

 

koo. Thanks. Well the IACV has been replaced once already by honda. just now on my way home, the CEL came on and the idle jumped up to 2000. I think when it does this and I pull the iacv it does drop I'm not sure though. But I know if the CEL isn't on, and then i pull the iacv... it jumps to 2000... wierd. I think it has something to do with vacuum leak or something now. could a b&m fpr cause this?

 

Make sure you don't have the plug for the evaporative purge control solenoid and the plug for the IAC mixed up. That would explain why it would jump to 2000 rpm all of the sudden because the evap purge control solenoid turns on after the motor has warmed up.

 

OK I'll check that but I doubt that's it. Oh and btw I checked out my idle thing when the CEL comes on... it jumps to 1500 and bobs to 1700 back and forth really quick that's what happens... not 2000-2200 like i said. Hope that helps.

 

**** i wish mine wasnt trippin. im doing the opposite of CivicRyda2k, my idle drops to 2-500 rpms and sometimes stalls out. it sucks. im throwing code 14( which i replaced twice even though they work) code 3, code 7. man its gotta be the ECU. im going to buy one. but maybe ill check to see if my sensors are plugged up backwards or something. i dont know what to do.

 

Uhhhh yeah, ummm did you get that memo about the TPS reports?

sorry, the first thing i thought of when i read TPS.

 

before u buy one... try to borrow one and check it out.

 

CivicRyda2K, isn't your car under warranty?

 

car will be at the dealership in 7hrs (8:00 appointment tomorrow). The reason I'm still posting trying to fix the problem is: a) i've taken it to one dealership already and they replaced the iacv and it still is messing up. b) maybe it's something simple c) maybe it's something I did and then when I get to the dealer they void my warranty or something. Oh well tomorrow i'll see. I told them I just want to get it fixed whatever the cost. As a side note... I'm going to a different dealership (scew Maroone Honda).

 

Which code are you getting exactly? Is this an 00' civic? Auto or manual trans? If it is an idle control code you could have an air valve leaking. 99-00 civic Ex's have a valve that lets air pass by the injectors. This valve is activated by coolant temp and is essentially a calculated vacuum leak. Your idle is always too high correct?


[Modified by fixhondas, 4:46 PM 5/13/2002]

 

Was getting code 14: Electronic Air Control/Idle Air Control Valve. Just got back from the dealership. They almost voided my warranty cause one of the guys figured out I had nitrous on the car (damn holes in the trunk... i knew I should have filled them). Anyway, according to them something is shorting out in my "A/C Clutch" circuit. They know FOR SURE... something's wrong with it. Which is what could cause the fluctuationg idle. Next, the guy also said my throttle plate was bent. The only thing I could see that could cause this is once when the nitrous backfired. I've heard of it damaging MAP sensors when it does that also so it could be a possibility. The tech's didn't get finished checking out the car because they found that the car had been modded and could have possibly cause all these problems. But the guy was cool and didn't let them void the warranty. Anyway so now my problem really is either a bent throttle plate, or a fucked up A/C circuit. Today I'm going to try unplugging the a/c compressor to see if that could be the problem. Hope it works because that would isolate the problem to the A/C which would make it much easier to fix. Knowing my shitty *** luck though... it will be something more complicated/expensive/headache-causing.

 

I have run into the A/C compressor clutch relay sticking on these civics- it will usually cause a rough shuddering idle because the compressor pressure is high and the ECU is not compensating for it (it doesn't know it is on). A bent throttle plate will give you a hunting high idle all the time. I have also seen sticking MAP sensors on the civics which can cause intermittent problems. Some freeze data would be helpful. You can unplug the one pin connector at the compressor to eliminate it.

 

Where's the one pin connector? All I see is a 2 connector harnesses on the fan. Also, the car only idles like this with the a/c off. with the a/c on... the idle randomly "jumps" up to like 1500 then right back down to normal.

 

You will see a wire coming from the A/C compressor going to the condenser fan shroud. It is a one pin connector that is further down from the two pin connector you are referring to. When your idle jumps- does it continually hunt up and down? Does the compressor ever actually engage? If the A/C compressor is commanded on and the relay or compressor clutch coil doesn't work (for instance) the idle will rise because the ECU is anticipating a load but the load is not there. This would essentially be a vacuum leak induced by the ECU. First thing to start with involving idle problems is to set base idle. Warm the engine up fully (fan comes on) and disconnect the IACV (provided you have a 5 speed Ex). Use the idle screw to set the base idle at 500 rpm. Can you accomplish this?

 

Does the compressor ever actually engage? If the A/C compressor is commanded on and the relay or compressor clutch coil doesn't work (for instance) the idle will rise because the ECU is anticipating a load but the load is not there. This would essentially be a vacuum leak induced by the ECU. First thing to start with involving idle problems is to set base idle. Warm the engine up fully (fan comes on) and disconnect the IACV (provided you have a 5 speed Ex). Use the idle screw to set the base idle at 500 rpm. Can you accomplish this?[/QUOTE]

OK i'll check for the one pin connector today. last nite when i looked it was kinda dark and i really didn't look well, maybe i missed it. and yes I know what you're talking about the adjusting the base idle. Now about the idle, if the a/c is off... and i revv the motor... when the rpm starts coming down from the revv... the needle goes like this:

revv the car to say 3000rpm:

- with the a/c off: on the way down... the needle dips to about 1000rpm (not sure if this is the exact point) then it jumps back up to 1500 then slowly goes to 1100ish then back up to 1400ish, then back to 1100, then after doing this a couple times, it slowly setlles to normal (around 700-900rpm).

- with the on: I really haven't checked out the revving deal with the a/c on. BUT... the idle acts WEIRD when the a/c is on. When I turn the a/c on at first the idle jumps up to about 1200 then goes right back to normal. If I'm sitting at a light with the a/c on for a couple of minutes, the idle jumps up ocassionally to like 1200-1500 then drops right back to normal. I observed this over like a 30 minute period once also. It did it like every couple minutes or so. Also, sometimes while sitting at idle with the a/c on, the a/c will start to blow HOT air.