95 Discovery Acting up! $ spent and to no avial! Stumbling/misfiring.

[AtlasEngr]

I purchased this 95 Disco about 8 months ago, used if for about a month after I bought it and tested a couple of things to try and pin-point the misfire. The previous owner had installed a new ignition coil, stepper motor, fuel pressure regulator, and passenger side O2 sensor. The truck was sold to me with code 45 being shown on the diagnostic box. I since installed a replacement distributor and waterpump.

There was a small leak on the passenger side manifold flange so I bought a new gasket and put it in. I installed a new center muffler as well. It currently has not catalytic converters either-- though I have some new Catco's in the garage for it.

I recently took it to an engine diagnostic test shop and they did a compression check, ignition check, fuel pump check, and sensors check. Well the shop said that the fuel pump was ~10psi less then requirement and said that was my problem. So I just replaced the fuel pump and fuel filter yesterday.

HERE IS WHAT IT STILL DOES:
-I will turn the vehicle on successfully and run for about 10-15 minutes.
-After the initial time, it will start to loose power and stumble, stutter, & misfire real bad.
-On occasions, I have had the tachometer and speedometer go crazy during the stumbling and misfiring.
-Then I will slow down, try to get back home at about 20-30 miles per hour (feels like engine is running on 2 cylinders) and shut the engine off.
-I will turn the engine on after a couple minutes and it will fire up and I check the temperature at each exhuast manifold location and all are about the same-- showing that the cylinders are firing equally.
-At times when it dies, it will not fire back up without hooking up my portable battery power pak.

Would this be the alternator, VSS, or some other sensor? I installed a replacement TPS sensor as well and still have this issue and code 45.

What do I check and how do I test?????

Stummped!!

[Elemental]

The tach signal is taken from the diode pack. If the tach is falling out, and you need a jump start to get the thing going....Your alternator is kaput.

[S1discoinSC]

I also have a 95 model and experienced...SOME of what you described. What I did was replace the altenator AND made an interesting find regarding the wiring harness plugging into the in tank Fuel Pump. It was loose to the point of just barely making any contact, plus it was fairly corroded.

Just a random thought w/ your loss of power and misfire issues.
Wish you luck!

-Mike

[Rovin4life]

got the belt put on right, seen a misrouted belt cause problems.

anyway how is 10 percent less.

what were their specs.

give me some numbers so I can help you.

[AtlasEngr]

Originally Posted by Rovin4life

got the belt put on right, seen a misrouted belt cause problems.

anyway how is 10 percent less.

what were their specs.

give me some numbers so I can help you.

They told me it was running approximately 10 PSI less. According to the manual, fuel pressure should be at around 35PSI.

Like I said, I insalled a new fuel pump but haven't checked the fuel pressure now. I drove it last week around for about 25 miles without A/C or lights on and it was running pretty good. When I turned the A/C on and lights, it slowly started to act up again. Lack of power and misfire -- taking it's sweet time to get to the next gear. Since I started it up for that cruise, it did not show a code 45 on the diagnostic code display. When I turned it off and attepted to turn it back on, it would not start but code 45 was right back!!

I tried to turn it on 5 minutes later and it fired right up but was definitely back to it's misbehaving self.

The previous owner had installed a new O2 sensor on the right side (pass.) bank. I don't know whether to buy another new Bosch O2 sensor or sell the darn Rover off and have someone else figure it out!!!!

I'm getting tired of this truck and need to find a fix for it. Otherwise, I am going to sell her off for next to nothing!!!

[me.guevara]

You need to check your alt. The symptoms you describe are exactly what happened to me when the alt stopped producing energy. While your battery is charged, everything works great, but hit the accelerator (requiring more juice at the cylinders) or turn anything on, cough, cough cough, sputter...

[Craig]

Some may remember last year mine was an identical problem. In the end the truck just died, turned out to be the fuel pump relay (very cheap to replace too)

[afirover]

buy a yoda