american_zero
NAXJA Forum User
- Location
- San Jose, CA
Hi guys,
My 94 4.0/AX-15 died yesterday and I have been unable to track down the cause.
I was driving home after a few hours wheeling and when I tried to accelerate quicky from about 45mph, the engine missed/backfired a little. I left off the gas resumed cruising and then tried again, same thing. Then the Jeep started bucking/missing really hard with any load on it. Had to slow down and pull of the side of road where it then died.
I started to diagnose things and here is what I have.
I have spark. At first I thought the fuel pump was intermittent and would work after I hit the tank a few times with a hammer. Now it seems fine and I have good pressure to the rail. The Jeep starts right up with some starting fluid in the intake.
I checked the injectors and it looks they aren't getting any signal to open while cranking.
What sensor controls the injectors? I replaced the crank position sensor about a month ago. From what I understand though, if the CPS was out, there would be no spark as well. I checked the plug at the ECU and it was clean. The ground wire connections all look good, too.
At this point I am thinking its the camshaft position sensor inside the dizzy. Considering throwing in a rebuilt dizzy, but would like to narrow it down a little more before I put any money in the heep. :wierd:
Thanks for any help guys.
Chad
My 94 4.0/AX-15 died yesterday and I have been unable to track down the cause.
I was driving home after a few hours wheeling and when I tried to accelerate quicky from about 45mph, the engine missed/backfired a little. I left off the gas resumed cruising and then tried again, same thing. Then the Jeep started bucking/missing really hard with any load on it. Had to slow down and pull of the side of road where it then died.
I started to diagnose things and here is what I have.
I have spark. At first I thought the fuel pump was intermittent and would work after I hit the tank a few times with a hammer. Now it seems fine and I have good pressure to the rail. The Jeep starts right up with some starting fluid in the intake.
I checked the injectors and it looks they aren't getting any signal to open while cranking.
What sensor controls the injectors? I replaced the crank position sensor about a month ago. From what I understand though, if the CPS was out, there would be no spark as well. I checked the plug at the ECU and it was clean. The ground wire connections all look good, too.
At this point I am thinking its the camshaft position sensor inside the dizzy. Considering throwing in a rebuilt dizzy, but would like to narrow it down a little more before I put any money in the heep. :wierd:
Thanks for any help guys.
Chad