Hi all,

So I'm going to summarize the current state of my recently purchased blazer!

This is a 4WD 2-door automatic from 1998 with 250,000 km, European import.

I have a work history since 2019 so I'll just note things down
interesting:

2020 235000km camshaft + timing kit + rocker arms + mass air sensor +
camshaft sensor + crankshaft sensor +
timing cover and gasket

2022 242000km 4x4 management module + transfer box engine +
4x4 control buttons + transfer case sensor

2022 " " " fuel pump (SKP) + fuel filter + air flow meter

2023 " " " ethanol box installation + timing cover gasket +
knock sensor


Then I bought this Blazer with an ignition problem among other things.


2024 250000km Removal of ethanol box + fuel filter + Spark plugs + spark plug wires + Cover
distributor rotor + ignition coil
Ignition timing (was off by one tooth with code P1345)
+ Fuel tank cap


This is what has been done so far.

The diagnosis shows me:

P0147-02 SENSOR HEATING CIRCUIT (BANK 1 SENSOR 3)

P0300 - Random/Multiple Cylinder Fire Misfires Detected

P0325 - CONNECTION 1 SENSOR CIRCUIT

P0452 - EVAPORATIVE EMISSIONS CONTROL SYSTEM LOW INPUT PRESSURE SENSOR

I will provide updates on the progress and resolution of the issue. problems. Thank you for reading me.

 

Welcome. Looking forward to updates!

 

Thank you, and all your suggestions or ideas are welcome of course!!

Edit: Additional informations: the idle speed is bad and the engine light flashes randomly when you go up in rpm but not at low speed. And for finish, cold start is very difficult sometimes. Thank you!!

 

I was able to test the fuel pressure, I'm at 49 psi the first time I turn the key, 55 psi the second time, then it drops very slowly. I read on the forum that the pressure should be 66 psi. the fuel pump was replaced in November 2022 by an SKP -SKEFP025-
already dead perhaps?

 

Pull the fuel filter and blow through it from the inlet side, there should very little resistance. If there is resistance, throw a new on in and retest the fuel pressure. I almost went straight to replacing my fuel pump a few years ago but checked the filter first. Ended up saving me the price of another fuel pump and the hassle of changing them out.

 

Hello,You are right, start with the simple things before going further. I didn't specify it but I replaced the fuel filter and inspected the line before performing the pressure test. Thank you.

 

Hello,

following the work on my blazer, this weekend I replaced the fuel pump which was a little over a year old and had been running on ethanol. now the vehicle starts fine.

Then I had a horrible rolling noise which appeared randomly in the front axle, so I started by changing the right CV axle which was damaged as well as the hub and bearing. Unfortunately the noise is still there or even worse than before. Maybe I'll look into the front drivetrain now.

I've registered this video before the replacement of the parts and you can clearly hear the sound.

Has anyone ever heard something similar on their truck?

 

Hi all,
following my work on my blazer, concerning the rolling noise in the front axle I replaced the CV axle and the hub without success. I had an extra front axle sold with the blazer so I decided to replace the 4x4 system actuator and it was indeed the culprit.
The gear was dead. All I have to do now is solve my p0452 and my p0325 probably the two are linked. to be continued...

 

Hi everyone,

investigation continues on my blazer with codes p0325 p0300 and p0452.
I analyzed this with the diag tool and the misfires mainly concern cylinder n*5.

The knock sensor wiring is good, it shows me ~5v to ground.

To eliminate the hypothesis I asked a garage to relearn the crankshaft sensor.

The SES light flashes above about 50km/h I guess because of the misfires.

As soon as I can I check my spark plug n*5.

I am considering replacing the injectors, my blazer has 250,000km, what do you think?

 

Before you start chasing misfires make sure that your cam sensor retard is within spec. Do you feel the misfire?

George