• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

CPS?

mecompco

mecompco

NAXJA Forum User
Location
Fairfield Maine
Well, I've read a dozen threads about the lowly CPS, but this is weird.

Jeep ran fine this morning. This afternoon, it would stutter and stall in Drive. Would start fine, every time. Would run and drive fine in Reverse. Would idle in Neutral. As soon as shifted into Drive it would buck, stutter, and stall.

Let it sit for three hours and now it is fine.

Now, it was under water a few times a couple days ago, but ran fine during and after the water crossing.

Any ideas?
 
Could be your coil,dist cap, wires ect. Did you dry everything off? Check all sensor connections and report back.
 
So, my understanding now is that the CPS has NO WAY of knowing what gear the tranny is in. Therefore, what could be the cause the strange behavior?

Cranks fine
Starts fine
Park--runs fine
Neutral--runs fine
Reverse--runs fine
Drive--bucks, stutters, and stalls

TPS doesn't care about tranny selection, AFAIK.

My NSS is good, and there is never a problem cranking or starting.

Had the distributer taken a drink, I would think it would have been apparent during/shortly after the water crossing. Jeep ran fine the rest of the day, the next day, and the morning of the next day.

Any more ideas? Thanks!
 
Did you check your NSS? I'm just wondering what it would do if you got some water in there...?

Just a shot in the dark, but maybe disconnect the neg battery cable for a bit and let everything reset?

That or just start getting really good at driving in reverse :D
 
JNickel101 said:
Did you check your NSS? I'm just wondering what it would do if you got some water in there...?

Just a shot in the dark, but maybe disconnect the neg battery cable for a bit and let everything reset?

That or just start getting really good at driving in reverse :D
Click to expand...

Cranks fine, so NSS is OK--the problem only occured in any of the forward gear positions (D,3,12).

Very strange. Anywho, it worked fine on the drive into work this morning. I just really dislike problems that "fix" themselves.
 
mecompco said:
So, my understanding now is that the CPS has NO WAY of knowing what gear the tranny is in. Therefore, what could be the cause the strange behavior?

Cranks fine
Starts fine
Park--runs fine
Neutral--runs fine
Reverse--runs fine
Drive--bucks, stutters, and stalls

TPS doesn't care about tranny selection, AFAIK.

My NSS is good, and there is never a problem cranking or starting.

Had the distributer taken a drink, I would think it would have been apparent during/shortly after the water crossing. Jeep ran fine the rest of the day, the next day, and the morning of the next day.

Any more ideas? Thanks!
Click to expand...

Mine did the same thing and could'nt figure it out. It sat for three months, being it was winter and did'nt look close but it ended up being my CPS loose on the bellhousing.
 
MiNi Beast said:
Mine did the same thing and could'nt figure it out. It sat for three months, being it was winter and did'nt look close but it ended up being my CPS loose on the bellhousing.
Click to expand...

It does seem like the likely culprit, even given the strange behavior. I do have a used spare--not sure if I should use that one or just buy a new one and replace it--would much rather do it in the garage than out on the trail.

I am wondering if these are effected by water. I do recall one other instance when the Jeep did a similar thing--bucking/stuttering for a moment (worked right out of it) this winter when we also did a water crossing earlier in the day.
 
mecompco said:
It does seem like the likely culprit, even given the strange behavior. I do have a used spare--not sure if I should use that one or just buy a new one and replace it--would much rather do it in the garage than out on the trail.

I am wondering if these are effected by water. I do recall one other instance when the Jeep did a similar thing--bucking/stuttering for a moment (worked right out of it) this winter when we also did a water crossing earlier in the day.
Click to expand...


Try your spare first if you know it's good. But anything electrical can be hurt from water.
 
had that happen on a friends jeep and it ended up being a bad cps wire and a bad motor mount. seems in drive the motor would twist on the bad mount and unhook the connection to the cps just enough to mess things up
 
You must log in or register to reply here.

Similar threads

A
Rough idle & CEL with no codes?
Replies
10
Views
3K
alopeks
A
V
High temp woes
2
Replies
21
Views
399
Vitzaa
V
1
AW4 Harsh Engagement
Replies
4
Views
2K
acruz95
A
J
Cranks, Fires, Dies - 1991 Briarwood Restoration
Replies
17
Views
3K
Jam Master Jay
J
XJJeeper59
Electrical:: Need Help from the Team
Replies
6
Views
2K
XJI6191
X
Back
Top