Ok, ready for this one? It may be something simple, but here goes.

A couple months ago, I was tooling down the freeway, with my wipers on delay. Not everytime, but about every 6-7 cycles, when the wiper starts, the engine skips. Doesnt die, but skips. After a few times, the SES light comes on. If I kill the truck, the SES light goes out, and it quits for the most part.
A month ago, it died right on the street, no wipers involved. I could get it to idle a few moments, then it would die again. After trying a while to keep it running, I got going, and it behaved the rest of the week. I do have a Bullydog 4 bank chip, and turned it down to stock, but it seems to do it on any setting. Now it does this at weird times. No real rhyme or reason to it, hits a lot one day, and doesnt reappear for a week. Today, it jerked, spit, but never completely died, and I could stay on the road. I cant helping thinking something in the bank is going bad, or my ECU is starting to tank. It acts like something is spiking voltage, and the whole truck is paying for it. Wiper switch shouldnt be the problem, it is doing it now when the wipers are off.

Any ideas at all? I thought maybe a cam sensor also, but thought these failed quicker...

Appreciate as usual!
Digger T

 

My previous truck did this... 2000 F350.

Thought I had taken care of it when I removed the inline fuel filter that was plugging.. Apparently not as the new owner has the same issues.
He replaced the CPS so far.. Hes about to replace the fuel pump. I'll let you know if the fuel pump fixes it.

 

Ok, that would be great. It might be the pump, if it happens on the fly, and it goes beyond one "spit", I can keep it going by flipping the throttle. I am still baffled how a 12v spike can do that, but hey, I am just a dumb firefighter, not a tech. Sides, thats why I am here!

 

I'm thinking CPS,always good to have a spare. The batteries absorb voltage spikes pretty well.
Nut

 

How about a severly overcharging alternator? I've seen VW gassers do that and the alternator was going crazy at 18 volts.

 

Can the CPS take a while to die? I thought they went bang right now. How does the wipers play into it?

 

I didnt check the alternator Kwik, I will check tomorrow. I did replace it a few months ago. Would that let the truck jump like it does? Thanks!

 

Yes, they can do weird things like be intermittent or die outright. Not sure
on the wipers.
Nut

 

Think of it in terms of overclocking a computer. You can push it a little, but go to far and it simply locks up.
The ECU is a computer.

 

That jump,or skip,(very unsettling) is classic CPS problems. Had mine do that cruisin down the freeway. Replaced CPS...no more problem.

 

the CEL is a very useful tool to figure out your problem. have it scanned and i will bet that you have a cps code in there. those are classic signs of the cps failing.

 

I believe quite often u don't get a code with a failing CPS so the dealer sets up
a take along monitor to diagnose bad CPS.But this time it might be the case!
Nut

 

Cool, thanks all for the info. I will check the voltage, and that unsettling "skip" sure sounds like it. I still jump, especially in the AM when the coffee hasnt kicked in yet. I dont think my Bullydog will let me run a code, but I am not sure on even that.
Thanks a bunch!

 

That ECM should have overvoltage protection( a voltage regulation circuit).
Nut

 

Guys, I realize this thread is extremely OLD.....but today my Late '99 started this, and I thought I remembered seeing a thread on it, just didn't realize it was 7 years old!

MY truck did exactly what the OP described when running the wipers on the intermidnt setting today about 6 times.

MY original CPS was replaced under the recall with the "first" GRAY ones.....and I have 2 GRAY ones in the glovebox.......I'll have to check my ticket from the recall but I'll bet I've run 50k with the GRAY one....

We still thinking CPS is the problem? any ideas as to why the wipers being on would cause this?