Chevy Trailblazer SS Forum banner

1 - 20 of 24 Posts

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #1
Help me. I have a 99 s10 with a 2.2 5 speed. It was needing a clutch so yesterday me and a friend tore into it. I have done 10 or more in the past, it's a really simple clutch to do. The clutch swap went fine had no issues or problems. So I go to start the truck and it cranks for a second and then nothing. The starter was just clicking. So I pull the starter down try to crank and still nothing. Removed the starter and bench tested still just a click. Replaced the starter today and truck turns over but will not start.

I listened for the fuel pump and it is indeed running. So I then go to the schrader valve and push it down and have no fuel. I cycled the key many times and still no fuel. I push down on the valve and had my friend cycle the key and I got a little fountian of fuel but barley any pressure.

I finally got the truck to start but it is running like shit. Missing. So I pulled it out of the shop and drove around the lot a bit and the check engine light starts flashing. I shut the truck off let it sit a min and start it back up for a road test and didn't even make it out the gate and it dies on me and will not start back up.

The truck has always ran great for me and have never had any issues. Is it just my luck that the starter and fuel pump shit the bed on me at the same time after installing a new clutch or is it something else?
 

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #3
I'm trying to find one. I don't have one myself. Priced a pump and it's almost 300!
 

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #5
All three grounds from the passenger side are on and clean I checked them first when I was having starter issues. I looked at the harness going over the top of the bellhousing and didn't see anything. I taped the wires up to keep from pinching anything. The only thing I keep thinking is a weak fuel pump.
 

·
Premium Member
TrailblazerSS
Joined
·
2,012 Posts
Knock sensor? Friend of mine blew up his 2.2 in his s-10. So we swapped it out for another 2.2. The fuel pump would prime but it would not start. Had to pull the engine back out, we couldn't get to the sensor because it hit the crossmember.
 

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #7
Which side is the knock sensor located on?
 

·
Premium Member
TrailblazerSS
Joined
·
2,012 Posts
Passenger side in the middle of the block near the oil pan. Its a pita to get to and is made of plastic.
 

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #9
ok thanks.
 

·
Premium Member
TrailblazerSS
Joined
·
2,012 Posts
Note that the 2.2 that im talking about was in a 1996 S-10, i dont know if they moved it in later years. I wouldnt think so but you never know.
 

·
Premium Member
'08 TrailblazerSS
Joined
·
4,146 Posts
Knock sensor has NOTHING to do with fuel pressure. Keep going down the diagnostic path you are on. Need to verify the fuel pressure. If the pump is running chances are there is no wiring damage. Looks like the pump just took a shit at a bad time. It's been a while since I've looked at that fuel system but the fuel pressure regulator could also be leaking down.

The check enigne light is blinking most likely from the misfires of running lean.
 

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #13
Oh ya I've owned 6 s10. It's about all I've ever owned except the ss. But today I walked out and the truck fired right up no problem and seemed to run alright.:dunno:
Check engine light is still on I'm guessing due to the lean miss last night. It's at work now so I'm gonna try to get it home so I can hook a scanner up to it and check my fuel trims to see if I'm still lean. I'm pretty sure I'll be changing a fuel pump but I want to rule everything out first before I pull the trigger on a 300 dollar pump.
 

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #14
Ok after letting it run for awhile it started missing real bad again. All I can think is I'm getting a lean condition due to a weak pump.
 

·
Premium Member
'08 TrailblazerSS
Joined
·
4,146 Posts
Ok after letting it run for awhile it started missing real bad again. All I can think is I'm getting a lean condition due to a weak pump.
You really need to put a fuel pressure gauge on it to verify as suggested earlier before buying a pump. I agree the pump is the most likely cause but it would suck to install a $300 pump and it being a $50 fuel pressure regulator causing the issue (not extremely likely but still possible).
 

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #16 (Edited)
I hear ya. I'm Gonna go buy one tonight. Pressure gauge that is
 

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #17
Alldata says: 41 to 47 psi engine running.

My findings:
Koeo- 45psi
Pressure drops off after pump kicks off.
Bad check valve in pump or injector.
Koer- 37psi
Weak pump.
 

·
Registered
2007 TrailblazerSS
Joined
·
432 Posts
Discussion Starter #19
From 45 to 0 in about 5 sec.
 

·
Premium Member
'08 TrailblazerSS
Joined
·
4,146 Posts
I'd say 85% chance it's the pump, 14% chance leaking fuel pressure regulator, 1% leaking injector.

The way we determine that from there is that we'll put a hose that has a gate valve inline from the fuel rail and the supply hose from the pump and another one on the return line. We command the pump on and off to prime up the system then shut off the gate valve on the return line to see if the pressure still bleeds down, if it does it's the regulator. Prime up the pump again and open the gate valve on the return line and close the one on the supply line, if it bleeds down like that, then it's a bad pump.

It would be hard to figure that out without the test hoses but given the percentages if I had to guess with a FP decay that fast that it's the pump. I really don't think it's an injector because you'd be flooding a cylinder and would have all the problems that go along with that as well.
 
1 - 20 of 24 Posts
Top