Hey everyone,

Cool forum! Hopefully you all can help me out some. My wife has a 1998 EX Accord 2 door, 2.3L and loves it but recently it has had some issues. I am very mechanically inclined and have always done 90% of the work to my family's cars. With that background here is what is going on:

She started the car last week and it started fine and drove it about 20 minutes away to a shop. When she came back out the car was completely dead. I suspected the battery just dropped a cell or something since it was about 7 years old I think. So I came and jumped the car with my trusty portable jumper and we were on our way home to get the battery out. Weird thing is the speedometer started freaking out and going dead, then coming back up to speed, etc. Well it finally has just quit working and registers nothing. I am assuming that driving it on only the alternator with a completely dead battery maybe fried the Varible Speed Sensor??? Low and behold the cruise control does not work either now, although that seems logical if the VSS is shot b/c that is what controls it. And the battery was the issue, I have a brand new Bosch in there and the car starts fine now.

Ok so that is the first problem, secondly the check engine light came on and the car (at some point, possibly not related) started idiling a little off. Before I did anything since the car hadn't been tuned up forever I did a complete tune-up. New plugs/wires/pcv/cap/rotor/etc. The plugs I pulled out of it were autolights, and gapped at around .060, way over the .039-.044 recommended in the manual, I don't know what that was about. So I replaced with properly gapped NGK's. I also added a bottle of Lucas fuel injector cleaner/conditioner to the tank that we are currently using. The old pcv valve that I pulled out was completely plugged as well, the new one is now in there. After the tune up the car is far more smooth and runs (while driving) fantastic, but the CEL is still on and the idle problem still exists.

I have a few theories as to what could be causing both, and they are not related in my thinking. First I had the code pulled at AZ and it was code P0420 "Catalyst system efficiency below threshold bank 1". From research people have said 90% of the time that means a bad catalytic convertor which is certainly on my list for the CEL. Here is how my theory is breaking down currently:

For the CEL I am thinking:
1. Catalytic converter
2. O2 sensor(s)
3. MAF
4. EGR
5. Vacuum Leak

For the idle problem (if it is not related to one of the things above) I am thinking:
1. Fouled fuel injector (one reason I added the lucas)
2. IAC valve (and I hear there is another "fast idle valve"?)
3. Alternator issue or possibly a fuse (after discussing similar problem with a person I know)

For the Speedometer / Cruise Control I'm thinking:
1. VSS Variable Speed Sensor shot (Could also be causing the idle problem from research I have found)

My problem now is I would only like to replace what I need to and not throw a heap of money at fixing every single thing as the cat and O2 sensors are fairly pricey (and no there is no way I am going to pay Honda 1000.00 for a damn catalytic convertor, are they crazy?). I am leaning towards the VSS first, it is 72.00 at AZ and "should" fix the speedo/cruise and possibly the idle, seems like the best/cheapest first shot try.

My question for you all, is my thinking fairly accurate for fixing these problems? Where should I start, is there something I am missing that could be the problem. Do you just start at the cheapest and go from there, or based on the reasearch do I just start at an aftermarket cat and see what happens. Would seafoaming the motor do anything possibly? Sorry for the long post but I want you experts to have all the info, really thanks so much for any help!

jason

 

For the CEL, you don't have a MAF sensor. I think that's true even for California cars.

For the idle, add to your list - adjust BASE idle & reset ECU. Between the spark plugs & everything else, it might be "remembering" the idle behavior from when it had bad plugs.

 

Jim, thanks for letting me know about the maf, what does the car use then to meter the air? Guess I'm used to Maf cars.

To reset the ECU don't you just remove the negative terminal from the battery? If so I have done that and still persists, what is the procedure for setting the idle? I found this post, is this the correct way?

https://www.hondaaccordforum.com/for...ad.php?t=25503

 

Hondas generally use RPM, intake-air temperature & intake-air pressure as the primary measurements. The air mass-flow measurement seems to be typical of European cars (I've had some Saabs & VWs) but more Japanese are using that now too.

Fusebox in the right-side of the dashboard (near the right-side door hinges). Pull fuse #13 to reset, I think that doesn't interrupt power to the stereo. Certainly pulling the battery will also reset.

Preliminary idle stuff...
Find & fix any vacuum leaks.
Remove any air-pockets in the cooling system. Really.
Throttle cable must go slack, the throttle plate MUST close completely.
The mechanical stop-screw on the throttle is only to just prevent it from sticking closed.
Clean any oily crusty carbon crud out of the throttle body & the IACV.

Find the idle-air screw - it's a brass screw #1 in the picture, recessed in a hole above the throttle bore.


Now set the BASE idle...
- warm the car up completely
- ALL loads OFF (AC, blowers, lights, EVERYTHING)
- unplug the cable from the IACV (you might have to nurse the throttle)
- adjust the idle-air screw for 550 rpm (if radiator fan comes on, wait till it shuts off)
- turn it off, reset the ECU, plug the IACV back in
- let it cool down completely
- start the engine without touching the gas pedal
- let it warm up completely without touching the gas pedal

 

Jim, thanks for the info. I am changing the VSS today to try to fix the speedo/cruise and then if that takes care of the CEL and Idle, great, if not I am on to the steps you laid out. Thanks again for the info, it is greatly appreciated!

 

Well just an update, I went to AZ to get the VSS I ordered yesterday and just for kicks I put the code scanner on it again, and low and behold my P0420 Code is gone and the VSS code P0500 is the only one in there which pretty much makes it the VSS bad so I think I'm good. The tune-up must have taken care of the P0420 code and that is why it is running so much smoother (glad I don't have to put a cat on right now). I'll report back after installing the VSS today and see if that takes care of everything.

 

I'd expect that a new VSS will not fix the surging idle. It's not a bad thing to check out the stuff I said, then adjust your base idle.

Some misguided mechanic might have messed with the idle screw while the IACV was plugged in, or maybe used the throttle-cable to increase the idle. Either one of these would have seriously confused the idle-control software.

 

Jim will do I'll report back thanks.

 

Just my $0.02 - when my VSS went out on my 2000 LX, I had a surging idle. I think the CEL threw the engine into "limp mode." I had the CEL with the VSS code, my speedo quit working, and my cruise would not work.
cfiiman - mine was on a manual trans car, but I think the VSS is similar on an auto. If you need help locating the thing, I did a write up in the DIY section. You are going to need about 3 feet of socket extentions and about three elbows to reach the thing from the top. Also, my VSS would not come out of the trans. I had to jack up the front end and spin the right front tire with one hand while yanking on the VSS with the other - it finally popped right out.

 

Well the new VSS fixed the problem!!! The speedo/cruise are back and the idle is perfect (I did reset the computer too). This thing runs like new, wish I would have done the tune-up a long time ago. But Jim just so you know, the VSS did definately cause the surge/shuttering on idle. Thanks for both of your guys' help, I really appreciate it, I just wanted to report back so if someone else has this problem they can find this post, thanks again!