wierd switch on the dash and backfire??
 

When I got my truck the previous owner had done some modding of his own for towing and I noticied a couple of switches on the dash section immediatly above the fuse cover one wasnt connected to anything and the other had some wires but I didnt really trace them that well. The switch with wires goes to something performance wise because when it is on I can feel a difference in the acceleration speed and I hear more turbo through the exhaust. I have always kept it on because I like the little bit of power it provided me but today I decided to switch it off and see if I got better fuel mileage or anything like that. After about 20 miles of driving I heard this real big "WOMB" almost like something rubber hitting a fenderwell, so I pull over and check everything I can and it all looks good. About 15 more miles and the same thing so again I stop...look...and it all seems o.k. so I drive to my friends house to look at it, and with it running I pop the hood and all of a sudden it does it again and the kwik filter and intake tube jump about 2" and then hit the fender.....Talk about scary!!!! then it dawns on me to turn the switch back on and I have driven 100 miles and it hasnt happened again...what in the world does this switch go too??? any suggestions??
I am lost!!
Brad

Probably a 10K mod.

Pop

I would trace that wire and see where it leads. If I didn't know any better it sounds like an unregulated propane feed going into your engine and it's backfiring through the intake. Either that or you have a sticking intake valve. But that wouldn't be enough to toss the intake around like that. It would be more of a rythmic chuff, chuff, chuff coming back up through the intake.

I agree with Kwik.....either propane, or maybe an ethynol injection.

that is realy strange, any chance of finding the guy you got it from and asking him?

Does the truck have any aftermarket gauges. If it does do you see any different readings with the switch on or off. I doubt its propane as you would have probably run the system dry by now, therefore no performance difference between the on and off position. Where did you buy the truck, maybe some one on here recently sold thier truck and would know what the switch is for.

I bought the truck 3 weeks ago in Houston Texas from Hussan motorcoaches, tommorrow I will check the wires and find out. I know its not 10K because I installed a 5.6K with a pontimeter on the dash and there was nothing there, and nope no aftermarket gauges. So I guess all that is left is to trace the wires.
thanks, Brad.

O.k. so I couldnt take it any more, I went and looked at the switch tonight and teh two wires (red and black) went to the Superchips gold plate on the front of the ECU. I was unaware that you could turn a chip on and off! that is so cool!!! the only problem is I looked online and superchips doesnt offer a chip for my truck, only a programmer???? what is up with that? is the chip only on/off or should it be wired in series for 1/2/3?
BTW how come I cannot post attachments for pics?
Brad

It's probably not on and off. I think it's more likely that it is high and low, but that's only a guess since I wasn't aware that Superchips ever offered a multi position chip.

Make sure the key is not in the ignition and remove the chip and see if it reproduces the problem. If you already have access to it, it just pullls straight out and should not require any effort.

Cool I will try that cookie, is there anyway to get a model number or anything to look it up online or call superchips? I would really like to know more about it!
Brad

having never seen a chip in person, i would guess that theres a serial number or some sort of identifier on it...its a piece of computer hardware/software, theres gonna be a way to identify it.

Today on my lunch break I pulled the chip out and the 2-wires went right into the back plate on it, but there were no numbers or markings or anything on it, just superchips on the front plate.

hhmmmm.....give them a call. they should be able to tell you something at least.

wayfastwhitey, must be a fan of Jesse james huh?

Crummy Trk, yes that man is my Idol, I hope he doesnt get mad that I used his name!! :-)

I guess I will have to call superchips to find out.