First off I'm new here - I stumbled across the site by doinga google search... but it looks like im in the right place!

Ok, here is the problem:

I was on my way home from work the other day (Chicago Area - Cold) and cruising the expressway and pulled into a gas station - I didn't get gas rather than just to go inside to make a purchase. As I pulled in the idle fluctuated between 1k - 3k for a sec luckily i had my foot on the brake as the car tried to go forward. I shut it off thinking it was just a fluke.

When I came back out the car gave me a little trouble starting - I had to give it a little gas pedal -I pulled out and the idle was surging a little bit then it seemed to go away. I got home in the driveway and the car surged and died.

I little later I started it up. Idle still surged but remained running. Took it for a short drive and soon as i let of the gas pedal it dies while in motion. I restarted it and it runs fine long as you place a little pressure on the gas pedal, as soon as you let off it dies.

There is no Check Engine Light on

So i figure it is the fuel filter and take it back home, to change it.

Guess what? still no luck and it seems like the problem is worse at it is having issues staying running while at idle and driving.


So instead of going through changing a bunch of stuff, I was wondering if anyone had this problem before or knows what it could possibly be?

Car Info:
97 Z34
120K+ Milage
No Check Engine Light
Car seems to run fine with littlegas pedal pressure
Acceleration is normal
Idle in my opinion is a little high - around 900ish
Timing Belt replaced 20k ago
Fuel Pump sounds good
When Running with foot on gas no hesitation

I was thinking Sensors, or Intake Leak, all vacuum lines seem to be on and not leaking.

So any help would be appreciative.

I dont have much experience working on the 3.4L but i have, built and repaired many other GMengines and cars - so working on it isnt a problem.I just dont want to spend a lot of time and money on fixing thingsthat dont need to be done.

This is my work car and I rather not invest alot of time and money into something that isnt really worth it.

Well i think i said enough for my first post so if you have any ideas let me know

Thanks,

Mike

P.S. I should have a scanner at my house tomorrow to see if that shows anything.

 

 

bascially what 'Space said... if it wasn't for the surging i'd say catalytic converter though. maybe an oxygen sensor is bad somewhere too?

the check engline light is worthless... when you have a problem, it doesn't come on.. when you don't, ti does (atleast thats how they work for me).

 

[align=center]
[/quote] [/align][align=center][/align][align=center]Hi `Mike, & Welcome to the Monte Carlo Family Forum.[/align][align=center]Every Monte Carlo is worth the time & investment : )[/align][align=center][/align][align=center]From just your written words, it sounds like it may be a[/align][align=center]dirty or bad Mass Air Flow Sensor, and maybe a bad[/align][align=center](IAC) Idle Air Controller ? [/align][align=center]This would cause a rev`in/idle issue with your Z
[/quote] [/align][align=center][/align][align=center]Well yes, the monte is worth it - but what i really ment its not worth putting alot of money into something thatI have owned for 11 years and worth about a grand ormaybe a little more. [/align][align=center][/align][align=center]Anyways I was able to diagnose the codes on the car and this is what came up PO102, PO306, and PO133 [/align][align=center][/align][align=center]PO102 - So guessing dirty or bad MAF (how do you tell?) and what should I do? [/align][align=center]Also when I was checking around I unplugged the MAF and it cause no changes???[/align][align=center][/align][align=center]PO306 - Misfire on 6 i cleared the code and it never returned [/align][align=center][/align][align=center]PO133 Slow Response Bank 1 - most likely and aged O2 Sensor - i dont think this is causing the problem that im currently having[/align][align=center][/align][align=center]I first thought the IAC but the voltage is reading correct on that so im guessing its not the IAC[/align][align=center]I also looked at the Catalytic Converter - while running it hasnt started to glow or anything so im assuming thats not it. [/align][align=center]I also have this strong odor out the exhuast - I dont know if its running to rich/lean or almost like a head gasket kinda smell - but i dont have any over heating or oil/water mixed as of right now. [/align][align=center][/align][align=center]Thanks for the input so far guys, [/align][align=center][/align][align=center]Mike[/align]

 

Ok one last thing a buddy of mine stopped by to take a look... (he used to own a monte)
He said he had this problem before and it ended up being the fuel regulator

He pulled the vacuum line off the regulator and the car idled smoothly - so does this make it the regulator?
Is there any way to tell - or is it still MAF related?Also there was puddling of fuel in the TB area- when we pulled off the vacuum line fuel was spitting out of the regulator.

I have a MAF sensor at the house now - but before i change it and can't take it back i want to be certain.

Any help is always welcome

Mike

 

Update:

Purchased a fuel pressure regulator from AZ $45.00

Changed it out - 5 mins

Car is back to normal

So it was the regulator after all.

Drove it 2 days so far all is well.

 

Can you tell me or snap a picture on where the fuel pressure regulator is located? The Chevy Dealership told me that the fuel pressure regulator was to blame.. they said 415 dollars for replacement. Yikes! I have a 97 Z34 motor. Thx man!

 

Great use of the search tool but unfortunatly i don't see you getting a picture froma 4 year old tread

 

And I had the exact same problem and fixed it by using a fuel pressure regulator.
This is a video of what it is in a 3.1 and similar to a 3.4
Thanks!

Fuel pressure regulator- GM cars and trucks - YouTube