Hi - my wife's 1997 Trailblazer 250 is doing some odd things I believe to be ignition related - but more specifically, I think maybe related to the switch etc. that retards the ignition when it is put in reverse or maybe the system that cuts out the ignition when it detects a throttle stickin.

The problem is intermittant - when not acting up - it runs perfect. But on occasion, it suddenly will act like it does when in reverse - like the ignition is retarded etc. In fact, on a few occasions I believe the reverse light has come on (yet clearly not in reverse). Through some experimenting, we discovered that if you push the "over ride) button that is designed to override the ignition retard when being in reverse, the problem will clear up for a short time.

Is this a common problem area? I assume it would relate to some sort of switch inside the "box" that the shift lever/arm goes through under the right front fender. At this point I have not torn that apart to check, but are there any separate fixable components inside? and finally - is there some way I can simply by pass this system? Could I for example simply pull the wires from that black box off the "junction box" under the front headlight area? All suggestions welcome!

Or...I am way off here and looking in all the wrong places!

Thanks in advance

Mike

 

mike sounds like your problem could be in the rev limiter or shifter switch. reverse limiter, not over rev. its the little black box you are referring to. there should be 2 on your bike. the 1 with more wires (1 is ylw, 1 is ylw/rd) is the voltage regulator. the first thing to check would be the shifter. nothing more than a micro switch looks like toggle switch. if the shifter ball wears the switch can become misaligned or the switch is just bad. have seen a few switches on the 96, 97 with problems. if you don't find anything here, very possible that its the blk box. hard to this type of problem by writing, but hope this helps. jeff

 

Try unplugging the black wire coming off the limiter.This should disable it.Then see if it still acts up.

 

Ok - so you are both referring to the "reverse limiter" (I am gonna get real technical here...just to make sure I am understanding!) ie....the doo dad that the shift arm goes through under the right front fender? Right??? Not "rev limiter" as in part of the broader ignition system right?

Assuming I am understanding correct - what ftwflh is saying then is disconnect the black wire off that doo dad (love them technical terms when you dont know the real names!) and see what happens. I will give it a shot this weekend.

I will let you know what the out come is!

Mike

 

The reverse limiter I am refering to is a little black box with 3 wires . unhook the black wire and see how it acts.