So the other day I was enjoying VTEC in my car and on my way up to redline (8700rpm) and the tach did something strange. At about 8000 the needle started to accelerated faster than the car was moving and my shift light (8400rpm) didn't come on. I shifted into the next gear when this happened but the tach was at about 9000rpm when I made the shift
This gets better. So I tried to recreate this and record it with Hondata Smanager software on my laptop. This time it didn't happen. No problems, shift light came on, and no crazy needle.
Has anyone ever experience anything like this? And if so, what is going on with my car?

 

Was your clutch slipping? Check your ground wire on your thermostat housing and then your transmission to frame.

 

The last time the clutch was slipping was with the Stock clutch and the car had 55,000 miles. At that time it happened at a much lower rpm about 5000.
I checked all the grounds, good shape. I also have grounding wires on the car so I don't think this is it.

 

Did a little test. On the way to the gym no issues. Cooler weather only shifted a few times before the full throttle test.
On the way home, it happened again, over 90 degrees outside. Car sat at the gym for almost 2 hours.
Can an over heated clutch do this?

 

heated clutch can do this.. clutch is starting to go out, i'm having the same problem after a few tuning passes.

 

Just thinking here but if your clutch was just slipping and the tach was going to 9 grand, shouldnt your shift light still work, you have a different problem and then maybe also a slipping clutch, you were thinking correctly in the first post. Where does your tach signal come from, stock ignitor, coil or your software.

 

if it was tha clutch then the shift light should still come on. maybe its a dizzy problem,since your shift light runs through that,and also on hot days the internals may heat up and malifunction. just a idea. do you know anyone with a good dizzy that you could borrow for a few days

 

I would check into electrical problems before replacing your clutch. Out here in the desert, I have all sorts of funny little issues with my old CRX when it gets hot out. Both my main relay and my turnsignal relay are going crazy...

 

More thinking, your shift light needs to know when to come on, so there is some electronics built in for that, some logic that tells the hardware that you are at redline, maybe your hardware is going out on you but knowing Honda Dizzys, borrow one first for a week or so.

 

So do I need #12 or #8? Or both?

 

Possibly #12, definately not #8, but check you connections in the wiring harness first.

 

problems with bouncing tachs in my experience have been with the ground on the thermostat housing.

 

#8 is most likely to be the culprit.

 

i would say the coil #12. do you know of anyone you can borrow one from? it can get expensive guessing at parts. also you can get them from advance or autozone for cheaper

 

I changed the distributor housing about two months ago because of a bad bearing. I wanted to replace everything but Honda no longer sells them that way.
If I replace #12 and #8 I guess that will be nearly everthing.

 

yup my first guess was dizzy my buddys hatch was doing this same thing his rpm gauge was acting retarded then eventually the car it self started hesitating come to find out the dizzy was going out on him changed dizzys and had no issues since

 

it could also be the igniter wires i know there was a write up on g2ic about cleaning the connectors and wires and using dielectric grease on them

 

i had a problem like this, it will only get worse and it was the ignitor chip which is #12 i ordered mine from rockautoparts and i had to modify it just a little bit but it fit haha, but i have no clue what motor my dizzy is from

 

if its boucing around, then yes, its the ign.. maybe the coil

but if it isn't bouncing and just starts to rev faster then what the car is, your clutch is going out..

 

True, I have seen some seriously bad ignitors. especially if the leads are bad.

I'd change both and be done.

 

if the clutch was slipping would it cause the shift light not to work? also if it was gonna slip then i would think it would be right after the shift or when vtec first engauged

 

depends, sometimes shift lights are dependent on the rpms which is directly controled by the ign module.

 

the pieces of the dizzy can be tested with a multimeter, the values are in the hynes manual, takes like 15 minutes and saves you from replacing the wrong parts.

 

Shift light is actual the "check engine" light set by the S300. Sorry, forgot to mention.

I already ordered all the parts at work. I got 11 years, 140,000 miles out of these parts, seems resonable. Now I'll have enough parts to have a distributor rebuilt, a spare. Anyone know where I can get this done?

 

The ignitor #8 controls the tach on this type of dizzy. The blue wire goes to the tach. One post mentioned using a multimeter to test ignition components, actually they are say the parts are not open, any resistance readings are unreliable.

IF, your software sees a gradual rise in RPM up to 8K, it will turn on the light, if the clutch slips and zips past 8K quickly, maybe the software is too slow to catch this and the light will not turn on, I dont know the clock speed of the software and hardware so I am only guessing. Dangerous test, but, can you drive approaching 7500 RPM, keep hard on the throttle, push in the clutch as though your clutch slipped, go past 8K quickly and see if the light comes on. Will the light come on if the clutch is in?? Dont blow your motor.

I am also wondering why are you going 8K RPM, isnt the powerband for HP and torque much lower than that, you are wasting time going beyond your powerband. You need a dyno run to setup your proper shift points.