hkerekes
Member
- Joined
- Mar 6, 2010
- Messages
- 48
- Reaction score
- 0
- Points
- 6
- Vehicle Year
- 1989
- Make / Model
- Ranger
- Transmission
- Manual
I have had a few issues with this truck that I have sorted but I can't fix or figure out this one. When the truck is cold it runs fine. The longer it runs the worse the misfire gets. The hotter the outside temp the worse it gets.
Going to work in the morning the truck is fine. Coming home the same distance it acts up. Idleing at lights seems to make it worse in the afternoon but smooths out a little once you get moving.
The timing is at 10 degree, fuel pressure is good cold and when it starts playing games. New plugs,cap,rotor,wires. There are no cats. The TFI,map sensor,IAC,ECT, 02 sensor and coil are all new. The TPS reads .9 and 4.9v. The IAC reads 1.8 ish and the ECT reads .6 ish when hot and it misfires. I dont think i have any vacuum leaks.
The wiring harness was hacked but I fixed everything that i saw and it really didnt fix/change anything. I checked the grounds and the problem has never gone away. There are no codes at all.
On a cold start it dies unless you give it some throttle. Once it runs for 15 seconds it will idle fine. On a warm day it does not do that. I have ran seafoam in the fuel tank and some in the intake. I used to have a bunch of spark knock ontop of the misfire. I fixed the spark knock so I do not believe that the current problem is spark related. The fuel pump is supposedly new but i have 33 psi at idle and 37 ish when you give it throttle so regardless it works.
It has valvetrain noise but it is intermittent. Starting it in the morning it will go away but once it warms up it comes back. The rocker arm shaft seems to be unclogged and the oil is fresh/clean. It previously was dirty before I bought the truck.
Any ideas?
Going to work in the morning the truck is fine. Coming home the same distance it acts up. Idleing at lights seems to make it worse in the afternoon but smooths out a little once you get moving.
The timing is at 10 degree, fuel pressure is good cold and when it starts playing games. New plugs,cap,rotor,wires. There are no cats. The TFI,map sensor,IAC,ECT, 02 sensor and coil are all new. The TPS reads .9 and 4.9v. The IAC reads 1.8 ish and the ECT reads .6 ish when hot and it misfires. I dont think i have any vacuum leaks.
The wiring harness was hacked but I fixed everything that i saw and it really didnt fix/change anything. I checked the grounds and the problem has never gone away. There are no codes at all.
On a cold start it dies unless you give it some throttle. Once it runs for 15 seconds it will idle fine. On a warm day it does not do that. I have ran seafoam in the fuel tank and some in the intake. I used to have a bunch of spark knock ontop of the misfire. I fixed the spark knock so I do not believe that the current problem is spark related. The fuel pump is supposedly new but i have 33 psi at idle and 37 ish when you give it throttle so regardless it works.
It has valvetrain noise but it is intermittent. Starting it in the morning it will go away but once it warms up it comes back. The rocker arm shaft seems to be unclogged and the oil is fresh/clean. It previously was dirty before I bought the truck.
Any ideas?
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