95 S10, missing, running rough, no power - please help! - S-10 Forum
S-10 Forum is the resource on GM S-series trucks, Suspension, engine information, Body Modifications, painting tutorials.  Modifications to suit every need, budget and whim

95 S10, missing, running rough, no power - please help!

Go Back   S-10 Forum > Engine and Drivetrain Tech > 2.2L - 2nd gen 4-banging
New User? Register Forgot Password


 
LinkBack Thread Tools
Old 03-14-2012, 09:01 PM   #1
Registered User
 
Join Date: Mar 2012
Posts: 5
Location:
User is: OffLine
95 S10, missing, running rough, no power - please help!

Hi everyone. I've tried everything and hoping that you folks have heard of this issue.

1995 Chevy s10, 2.2 engine with about 100K miles.


This is my dad's tru8ck and he was driving and it suddenly started to run rough. He got home and I looked it over, and it seemed to be fine, but still running rough.


I changed the spark plug wires, and plugs - and it ran a little better but still rough at idle and would not rev over about 2K. when I press the gas, I can hear it trying, but it acts like a governor - it'll rev up a little then the power just drops out and it starts to fluxuate up and down sort of like it's not getting fuel. under load it runs smooth and does not miss - but only to about a quarter throttle then it's it - it starts to idle up and down and I have to back off.

I've checked - so far...

Coils - replaced them both. Got a third and swapped them just to be sure.
Wires/plugs as well. (new plugs quickly carboned up)
Fuel pressure is in range and solid.
Cat converter is clear and no backpressure issues.
Fuel regulator clear, clean and dry.
No codes. Not even a missfire code (using a paperclip)
Replaced the MAP sensor just for the help of it.
Cylinder pressure test - a-ok.

My mechanic says that all PCM numbers come out okay, and that the PCM is communicating correctly. No codes, all sensors read within tolerances, and he says it's not misfiring - just running rough and weak as a wet noodle.

I've not checked the mechanical timing because of the whole cover off thing - I'll save that chore for last thing, I think.

I did notice that there are two sensors on the passenger side in front of the coil, one high and one lower and slightly further back (that one is not plugged in, not sure what it is and can't find a plug to fit it)

Any ideas?
Thanks in advance.
Mechanic couldn't check the mechanical timing.



. I also had to replace one of the coils, and that helped as well, and now it runs great on all cylinders - but still
Old 03-14-2012, 10:00 PM   #2
I Prefer Payne
 
payne4life's Avatar
 
Age: 25
Join Date: Aug 2010
Posts: 904
Location: Flint/Dearborn MI
User is: OffLine
Re: 95 S10, missing, running rough, no power - please help!

try a fuel pressure test. could be a bad FPR causing your to run lean.
Old 03-14-2012, 10:39 PM   #3
Registered User
 
Join Date: Mar 2012
Posts: 5
Location:
User is: OffLine
Re: 95 S10, missing, running rough, no power - please help!

Quote: Originally Posted by payne4life
try a fuel pressure test. could be a bad FPR causing your to run lean.
THanks, already did that. Honestly I thought it was the problem, but the pressure is in range and solid.

Also, it seems to be running rich, not lean. Soot on the plugs.
Old 03-14-2012, 10:53 PM   #4
Forum Dictator
 
What?'s Avatar
 
Join Date: Jan 2004
Posts: 19,900
Location: Hell
User is: OffLine
Re: 95 S10, missing, running rough, no power - please help!

Do you smell fuel? Possible fuel injector leaking.
Old 03-14-2012, 10:57 PM   #5
Registered User
 
Join Date: Mar 2012
Posts: 5
Location:
User is: OffLine
Re: 95 S10, missing, running rough, no power - please help!

Quote: Originally Posted by What?
Do you smell fuel? Possible fuel injector leaking.
Thought of that as well, nope.

I'm shaking my head, I've got to be overlooking something. Can the timing jump one tooth and it still run?
Old 03-14-2012, 11:10 PM   #6
I Prefer Payne
 
payne4life's Avatar
 
Age: 25
Join Date: Aug 2010
Posts: 904
Location: Flint/Dearborn MI
User is: OffLine
Re: 95 S10, missing, running rough, no power - please help!

Throttle position sensor?
plugged air filter? or something restricting air?
are all the plugs black or just one?
Old 03-15-2012, 04:31 AM   #7
Powder Coat Specialist
 
xtrememeasures10's Avatar
 
Age: 28
Join Date: Apr 2005
Posts: 2,717
Location: St Louis Area
User is: Online
Re: 95 S10, missing, running rough, no power - please help!

Quote: Originally Posted by Gideon
Thought of that as well, nope.

I'm shaking my head, I've got to be overlooking something. Can the timing jump one tooth and it still run?
Yes it can, it will run like shit tho, very little power. i would check it.
Old 03-15-2012, 06:45 AM   #8
Registered User
 
Join Date: Mar 2012
Posts: 5
Location:
User is: OffLine
Re: 95 S10, missing, running rough, no power - please help!

Quote: Originally Posted by payne4life
Throttle position sensor?
plugged air filter? or something restricting air?
are all the plugs black or just one?
TPS working great, no air restrictions, and all of the plugs are black.
Old 03-15-2012, 07:35 PM   #9
Registered User
 
Join Date: Mar 2012
Posts: 5
Location:
User is: OffLine
Re: 95 S10, missing, running rough, no power - please help!

Quote: Originally Posted by Gideon
TPS working great, no air restrictions, and all of the plugs are black.
New info!

I checked the sensors and the Crank Position Sensor was unplugged - but I can't find the plug! It's missing. I have MFI, and should have a plug for the sensor!

Or does it?
Old 05-22-2012, 04:11 PM   #10
Registered User
 
Age: 26
Join Date: Jul 2011
Posts: 1
Location:
User is: OffLine
Re: 95 S10, missing, running rough, no power - please help!

My truck is a s10 2.2 98, it was running really bad, it seems like governed, gas smell, hard starting, and sudenly stoped and i can't turn it on again... coil spark GOOD, 45 psi Fuel pump GOOD, inyector signal GOOD, Pressure in the cylinder ZERO psi... yes... timming chain. It was broken and that's why my truck started to go in that way, first the chain skip a tooth of the gear, that affect in hard starting, gasoline smelling and governed speed, when the chaing got broken the valves didin't work and the presure went to zero, me advice in this case... check te cylinder presure and the timming
Old 06-04-2013, 10:23 PM   #11
Registered User
 
Join Date: Jun 2013
Posts: 1
Location:
User is: OffLine
Re: 95 S10, missing, running rough, no power - please help!

i seem to be having the same problem.. i have a 98 s-10 and i have no take off power. when i reach 40 then it runs find. till i hit 70 and it starts bogging down.
Sponsored Links
Advertisement
 

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the S-10 Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 05:45 PM.

Powered by vBulletin® Copyright ©2000 - 2011, Jelsoft Enterprises Ltd. SEO by vBSEO 3.2.0
SEO by vBSEO
vBulletin Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.