I could really use some guidance on this one. My 03 Ex has 122K miles and is well maintained. just recently the gages have started going crazy. primarily when traveling at highway speeds, when the tranny downshifts to pass, the needles sweep both ways, all the lights light up then everyhting drops and then goes back to normal. Also the radio sound (not illumination) quits.

I can keep the gages in crazy mode if I keep the tranny in 2nd gear and accelarating. as soon as I let up and it upshifts, the gages settle down.

It also seems to occur if I go over some bumps. not always. that is more random. and I get a little misfire when that occurs, but no always.

My mechanic/friend was looking for a bad ground. pulled the fuse/gem tightened everything up. thought he had it then went over the RR tracks for a test drive and BAM! crazy gauges again. I pushed them this morning and hit WOT briefly and they went crazy.

I am thinking there is a loose ground somewhere, and it seems to be associated with the engine or tranny under heavy load. maybe a ground on th engine block or tranny that is loose and opens up when the tranny or engine torques a little?

wondering if anyone could find a diagram of the ground locations on an 03 Expy?


PS - I am a former member of the forum but my email changed, couldn't retrieve my user info... and so now I am renewed!

And I have searched not only this forum but the entire internet. seems crazy gauge syndrome is common out there.

any advice on where to look would be appreciated.

 

Im guessing bad alternator or battery. I would have them both checked

 

Do the gauges sweep at start up also ?

 

I would definitely have the battery load tested or if it is over 3 years old, I would replace it.

 

Battery is 2 years old. no issues at start up or while normal driving. in fact it drives great! even when gauges are possessed, it drives ok.

the alternator could be a source. hammering the throttle, downshifting causes the engine to spin up. However, if I sit in my driveway in park, and rev the engine, up to 4k sitting still (higher than it gets when downshifting to pass) it purrs like a kitten. no gauge insanity.

so to recap: gages go crazy almost 100% when downshifting to 2nd while driving, radio cuts out too. and sometimes when going over bumps.
otherwise truck starts and drives fine.

still thinking it is a ground shorting out somewhere.

could use a diagram of the ground locations if anybody has one.

thanks for your input again.

 

Get underneath with a creeper and follow the ground from your battery, starter and alternator, youll find them. Then take out alternator and have checked if your convinced your battery is fine, but my as well have it checked as well while your at it.

 

i am driving around with the fuse panel (psgr kick plate removed) open and can hear the relay clicking on and off every time the dash goes crazy. So i got my son to ride with me and just lightly hold his hand on the fuse block to see if he can feel which one is opening and closing. he finds that it is R02 - controls fuse 22, CB401 (whatever that is), and the accesory on function. I had replaced that as part of the diagnositc based on the fuse table in the OM. indicating both radio and other things related to the gage cluster.

So we stop the truck and swap the relays. the replacement unit was a cheepo from advance auto. it works, but does not seem to fit in as tight as the OEM.

low and behold, we take off and I cannot get the truck to have crazy gage syndrome. (well, just once, a little). after that one time, nada. so perhaps the relay had just become loose over time, change of season whatever, and the new relay was just not OEM exactly.

still need more testing, but I feel like I am a lot closer to JOY.

 

driving to work today i again got crazy gage syndrome. sometimes with just a light aceleration, or even just going up a small hill in town. anything that puts the engine under load.

on the highway, i began to have misfires with the slightest acceleration. had to drive like grandma's grandma on the way home to keep it from shaking apart. with minimal acceleration, it ran ok. just a little touch on the pedal and i got the misfires.

i've alos been having a problem with my EVAP system P0457 and just today, P0443. I can smell gas as soon as I start er up in the morning, or if I am idling at a light or whatever.

I am so frustrated. any advice would be greatly appreciated.

 

based on something i read online about COP's that start to fail and produce RF signals that feedback into the PCM and cause it to not work properly, and the fact that one of the ebay COP's had just failed (3 others failed on my v10 van), I replaced the COP's with Accel packs and new motorcraft platinum plugs. Also replaced the evap purge valve (probably unrelated problem which threw a code).

Happy to report that the gauge sweeping issue, coupled with rough misfiring, is completely gone! Seems like the cheepy ebay COP's did not like the increased voltage while under load and were faulting. during light load, idle and crusing they were ok.

I found the Accel COP's on Amazon for 189 with free shipping. the build quality seemed inherently better than the ebay packs, and at least as good if not better than the OEM packs.