00 GTI - bad MPEM?

[MxRacer965]

Hi all,

Been lurking around here as I just bought a 00 GTI this Spring and did some general maintenance like rebuilding the carb (clogged fuel filter), replaced all the old tempo fuel lines, fixed the fuel baffle resistor, pump oil, new beeper, etc. This forum has been hugely helpful so thank you all.

On to my situation that I could use some help with. It's been running great until the 4th of July when suddenly while cruising along mid throttle the engine started cutting out while I noticed the speedo fluctuate rapidly up and down with no rhyme or reason followed by the ski shutting off. If I press the start button I get a single beep unless I remove the lanyard and put it back on again and it starts right up. It may run fine or it may act up. I've had instances as well when the oil light will come on while all this is going on, and I've had the ski beep before as well. The only consistent symptom that goes with the cutting out is the speedo rapid fluctuations. So far it also seems to happen after more extended riding or when I'm out getting aggressive in the water with water splashing everywhere. I disconnected all connections and applied fresh dielectric grease and that didn't resolve, it has new BR8ES plugs (just in case) as well.

My first thought goes to the MPEM failing since it is the brains behind all the things that are going haywire. What are your thoughts?

I did get a new regulator that I intend to try this weekend to see if that might be it, but I'm not too hopeful. It hasn't been jumped since I've owned it. I did put the battery on a charger but it was out of the ski.

Anyway, any insight would be appreciated!

Aaron

 

[mikidymac]

It sure sounds like a bad electrical connection to me. I would double check a gain all wire connections as well as all the ground cables and terminals.

My cousin's 97' XP was doing the same thing, riding fine then all the sudden it would shut off and give one long beep when trying to restart. This long beep when pushing the start button is the MPEM telling you that it doesn't recognize the key. He would pull the lanyard off then put it back on and get the correct two beeps start it and after about 50' it would do the same thing. We have replaced the DESS post and that appears to have fixed it but haven't water tested it yet.

 

[MxRacer965]

Thanks for the reply. I'll double check them all again and maybe clean with cleaner first then re apply dielectric grease. I figured if it was connection it would be a bit more consistent in being inconsistent...

Obviously from a ground perspective the negative battery terminal but what other location(s) should I be looking at?

Thanks again!

 

[MxRacer965]

Cleaned and reapplied dielectric grease and still no luck. Battery checked out fine from a voltage standpoint, but it had 7/23/2011 written on the side! 6 year old battery it appears. I bought a new one and hopefully can try it this weekend. Any thoughts on if this could cause the erratic behavior? I did try the new regulator and it made no difference so I put the old one back on.