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Discussion Starter · #1 ·
I'll give you the story of events that lead up to these problems and what I did to try and fix them. About a week ago I flew up to NY and stayed there for about 5 days so my car sat at my dads for that time. I get back and drive it about 30 miles home with no problems. I was on E so I went and filled my tank. The next day I start the car and it has an irratic idle. Going from 1k up to 2k and back. I figure it might go away if I take it for a drive. I get down the block and the car doesn't want to go anywhere. I give it gas and it just doesn't go. It sounds like its misfiring. It backfires and bogs. I figure it might be my D16 dizzy going that I have been running on my B16 so I finally use this as an excuse to swap it for my new B16 dizzy which I got in the mail a little while ago. I swap it and adj the timing but that didn't solve the problem much. I let the car run for a bit to warm up and then adjusted the idle speed and got a timing light and adjusted the timing. When the car is warmed up it idles right at 750 and drives ok enough to get me around, but it still has a loss of power when driving and it boggs for a second then kicks in and goes. thats the best way I can describe it. So I think it might be a bad tank of gas since I just filled up. I let the tank run down and refill the tank but that didn't do a thing. So I next replace the fuel filter and O2 sensors since I knew the sensors were bad and I am not sure the last time the filter was changed, That also didn't do anything. Next I think it might be the EACV since the bogging and loss of power are simptoms of a bad EACV. I take the old one off and cleaned it. That didn't change anything so I replaced it with 2 other EACV's and they both didn't change a thing. I am also getting about 18 MPG right now. I am now at a loss of ideas. I'm thinking it might be the fuel injectors but I can hear them clicking so I dought its them. Any help or ideas would be great.

-James-
 

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Precisely.

While you won't be able to adjust anything, you can atleast read the output from the sensors to see if anything is "off".

You'll need a nokia USB cable. I'll try to give you a direct link. There's tons of companies that sell that stuff to "chip" ECU's and such.

Honda's ECU's are pre-wired to read them. They've been doing that since '88. But it took the "honda community" till 'bout '98 to figure that out :)
 

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Discussion Starter · #5 ·
what program would I use to just read the sensors. I have crome will that work? What wires do I attach the usb cable to. I'm starting to get aggrivated with this car. luckily I can walk to class so its not a major pain but I want it running perfectly. I just replaced the plugs and wires and swapped out the main relay for 2 others which turned out to be bad. I am looking into fixing mine because I have noticed some dry joints which I read could be the cause of my problems. Any other ideas would be much appreciated. I also have some oil leaks to identify. Looks like I better find a job so I can get the car running mint. Thanks guys
-James-
 

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The fuel injectors may need to be cleaned (this is my bet).

I would just do a normal tune-up. Might want to check valve lash too, even though I'm pretty sure that's not the problem.

My DX used to do that from starts every once in a while. I did a tune-up and it ran just fine.

After all of that, you may want to check with another ECU to make sure your ECU isn't bad.

It sounds like the car is running really rich.
 

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Discussion Starter · #7 ·
Yeah it is running really really rich. Good idea baout cleaning the injectors. What would I clean them in? Should I pull them from the rail and soak them in a cleaning solution? I used that injector cleaner stuff in my tank a couple days ago. I adjusted the valves about a month ago but i'll check them again just incase. Anyone in ohio that wants to lend me there PR3 ecu for a bit?
thanks

-James-
 

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From Heu:
Diagnosing and Curing Surging Idle

Maintenancedohcrxl writes: I noticed that the surging idle question gets asked from time to time and thought we could use my lil write up as a service to the community.

Three things I know and have seen to cause a surging idle:

1) air in the cooling system - when hot coolant comes in contact with the AICV (idle air control valve) it gives the ECU a reference as to what to set for an idle. The ECU then lowers the idle because it senses that the engine is hot. When it does that the waterpump of course slows down with the rest of the engine and is not spinning fast enough to pump a sufficient and constant flow of coolant because there are air pockets in the system preventing it. When that happens, the coolant that used to be in contact with the AICV now retriets, the ECU then senses that the engine is cold, raises the rpms, the waterpump surges and speeds up, pushing coolant back onto the AICV, and the cycle becomes endless.

2) bad Idle Air Control Valve - on the back of the IM and should have a blue w/yellow and a black w/yellow wire going to it. Cleaning the filter screen inside the AICV will help restore a more steady idle. To do so, you must remove the valve assembly from the throttle body and clean out with brake cleaner.

3) A leak in the throttle body or intake manifold gasket - with the engine running, carefully spray brake cleaner on the mating surface edge by the gaskets. If the engine bogs when you spray, there is a leak where you sprayed.

There is of course the possibility of leaking vacuum lines. If you don't hear or see any obvious leaks, unplug all the vacuum hoses one at a time. Each time after you unplug one, plug the exposed nipple at the manifold or throttle body with your finger. If the surging goes away you know it involves that line and or any component that line goes to. After you do this, put that hose back on and proceed to repeat that for each and every vacuum hose and it may uncover the problem. Another way to help isolate a pinhole leak in a vacuum line is to put your hand over the throttle body with the engine running. A leak will give itself away by the whistling it will make. Note* cover up only as much of the throttle body opening as needed to allow the engine to stay running yet force the leak to reveal itself. _________________
- Heu
You may also want to read this article. Good info.
 

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xJamesX said:
what program would I use to just read the sensors. I have crome will that work? What wires do I attach the usb cable to. I'm starting to get aggrivated with this car. luckily I can walk to class so its not a major pain but I want it running perfectly. I just replaced the plugs and wires and swapped out the main relay for 2 others which turned out to be bad. I am looking into fixing mine because I have noticed some dry joints which I read could be the cause of my problems. Any other ideas would be much appreciated. I also have some oil leaks to identify. Looks like I better find a job so I can get the car running mint. Thanks guys
-James-
You may also have a bad fuel injector. From what I'm reading it sounds like dirty injectors flow less fuel...obviously not your problem. I am also wondering if your MAP sensor is working properly. It could be reading a WOT condition causing your ECU to dump more fuel into the engine. Is this a stock ECU or something hacked?
 

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Discussion Starter · #10 ·
Its completly stock. The only things done to the motor are I/E/H and Type R cams with adj gears. I had originally thought it was dirty injectors thats why i put the cleaner in but you are right dirty inj won't dump more fuel in. How would I go about getting air out of the coolant system and how would air get in there in the first place?

-James-
 

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xJamesX said:
but you are right dirty inj won't dump more fuel in. -James-
Maybe it is not dumping more in but it could still be messed up. What if it has a lousy spray pattern so you are getting incomplete combustion. That would certainly kill you mpg.

I highly recommend Cruzin Performance.
 

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Discussion Starter · #15 ·
Ok I determind its not the fuel injectors, fuel pump, ECU or air bubbles in the coolant. So I was messing with it for about 4 minutes and I decided to just go over the vaccum hoses once more. So I unplug the MAP sensor vaccum hose from the throttle boddy and poof the car drives like a champ. a little high idel at about 1k when cold and it warmed up to 750+- a bit when warm. Now my question is shouldn't the ecu be throwing a MAp sensor cell. I'm off to my dads for dinner so we'll see how it does on a 20 min drive but I think its gonna do ok.

-James-
 

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Discussion Starter · #17 ·
Well I don't think that is true because after I pulled out the parking lot the check engine light came on and it was throwing a code 5 which is the MAP sensor. I drove to my dads with it on and the car drove fine just no Vtec. I eat dinner and get some laundry done and go start the car. The Check eng light was still on. So I shut the car off and pulled the hazard fuse for a bit. That reset the ecu. I start the car and it drives fine untill about 15 min into the drive the check eng light comes on again. I figure its the MAP sensor. I get to my apt and check the ECU and it is now throwing a 1 and 2 not a 5, these are the O2 sensors. Also the car was bogging a bit when I was going up a hill near my apt like it was doing before. I'm going to leave it as it is for now untill I can look at it this weekend. Oh and the O2 sensors are about 6 days old so who knows about that. Oh so now is the actual MAP sensor bad or is there somthing else wrong here?

-James-
 
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