I have an 89 CRX Si that has about 206k miles on the clock. I still drive the car every day to work and back as it gets great gas mileage (~41mpg average freeway @ 70mph with a light foot). Recently the car has been feeling a little rough, especially at low rpm. I also noticed it kinda smells a little burnt, so I pulled the plugs out and took some pics...

Gap is .40" on all four, and they are less than a year old (NGK V-Power copper). Distributor is new (with cap & rotor), plug-wires are 5-6 year old NGK blue 7mm. Injector #1 was recently replaced with a used one due to a leak...

Plug-1


Plug-2


Plug-3


Plug-4


Any advice would be greatly appreciated... -Sean

 

get new plugs....

 

looks like plug#4 is the one missing (misfiring). just because it doesnt look burnt up as much as the others. you should check plug wire on plug#4. switch with another known good spark plug wire (if you have any laying around), see if your problem goes away. by looking at pictures,looks like plugs still good, no need to replace just clean lightly, re-gap and reinstall.

 

Thanks for the tip. I"ll give the plug-wire a shot as I have a decent set laying around from my 94 Civic CX D15B8. They seem to fit fine...

Now if only I could get the alternator light to stay off at idle...

 

Dont look that bad. I have seen ALOT worse. Just replace plugs and wires...should be set. Good luck.

 

But I thought the plugs are supposed to have a brownish-tan color to them after use...

 

yes, you read the color on the ceramic. To properly read the plugs you shut the engine off while the problem is occurring. The white deposits are usually from gasoline additives.

They all look good, just a little cleaning should do. The plug wires are a bit old.

 

no prob, but lets work one problem at a time. whats the alternator light exactly doing at idle and off? but i guess thats a different thread, right?

 

the alternator problem could be causing the hesitation.

check the DC voltage at the battery when off, idling, and ~2krpm.
check the A/C voltage at the alternator when idling and ~2krpm.

 

Well the different plug wires seemed to help out quite a bit. I guess 8-9 year accell wires fair better than 5-6 year old NGKs (both similar econo-driving use).

BTW: Thanks for the tips on the white deposits. I only run Chevron gas which is said to have detergents in it. Other than that there is no additives...

As for the alternator. The light only comes on after it's warmed up. As I come to a stop and put the clutch in, the light comes on. Depending on how bad it is, it won't happen if there are electrical accessories on (headlights, fan, brake lights, etc). It seems to only happen when the alternator goes into "low-charge" mode as the ECU is directed by the electronic-load-detector in the fuse box (low rpm, low speed, low load). This is supposed to causes the voltage to drop, but the light only comes on at idle after warm-up. Pressing the brake makes the light go on and off as electric load changes...

Things I've tried:
- replaced the alternator
- replaced the battery
- checked all wiring between the alternator & ECU
- replaced the fuse box (with ELD)
- replaced the ECU
- tried parallel wiring all the engine grounds.
Nothing changes...

 

Here's a link to the old post with the voltage info while driving.

https://honda-tech.com/forums/showth...576&highlight=

 

I'm not at home right now, so I don't have my FSM, but I checked my other resources and if your wiring and load tests all checked out it says to replace the v-reg. You have done that (it's built into the alternator) so I'm left thinking that you have a corroded wire or ground somewhere. I'd say clean up your battery grounds, thermostat ground, and even the alternator bracket mounts (alt is grounded through the engine block and bracket). Probably would also be a good idea to clean up the alternator plug wires and power wire. Use emery cloth, followed by contact cleaner and a rag, and then liberal dielectric grease AFTER making the connections.

I would also recheck the A/C voltage at the alternator while the light is on. The alternator has diodes to turn A/C to D/C, but there will always be some leakage. The battery light is illuminated when the voltage is low and when there is excessive a/c. None of the tests listed by my aftermarket resources include an A/C leakage test. This needs to be performed at the alternator output post, the battery will dampen A/C.