Ford Ranger Forum - Forums for Ford Ranger enthusiasts!

Go Back   Ford Ranger Forum - Forums for Ford Ranger enthusiasts! > Engine Tech Forum > 6-Cylinder Tech > 2.9 Liter Tech
Forgot Password? Join Us!


Reply
 
LinkBack Thread Tools Search this Thread

  #1  
Old 11-21-2012, 02:16 PM
Sub74
 
Join Date: Mar 2012
Posts: 480
Default Why running rich?

My 2.9 is only getting 10-12 mpg

You can smell that it is running way to rich, what controls the air-fuel mix?

Yes it has stock gears and 33" tires but still I should be doing better on gas and you can smell the unburnt fuel
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #2  
Old 11-21-2012, 02:24 PM
Commander Sparkles
 
Join Date: Aug 2010
Posts: 9,037
Default

What year?

sent from my IPod using the FRF app
__________________
Truck: 2000 Ford Ranger XLT 4.0 4x4 ext cab
My Build Thread
Mod Ideas
Don't Forget to:
Create a Signature
Show your system

Mods: Brush guard|Front Hitch|Expo Roof Rack|Train Horn|Door/Dash/step/Hood Leds|2" lift|Rear Tow Points|On-Board Air System| 22" & 40" LED bar|and More!
Reply With Quote
  #3  
Old 11-21-2012, 06:32 PM
Sub74
 
Join Date: Mar 2012
Posts: 480
Default

Sorry it is an 88
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #4  
Old 11-21-2012, 06:41 PM
Learning to use the forums
 
Join Date: Nov 2012
Posts: 12
Default Re: Why running rich?

My 87 stx is doing the same thing, I get like 15 miles if I'm lucky and I can smell he unburnt gas..
Reply With Quote
  #5  
Old 11-21-2012, 06:42 PM
Commander Sparkles
 
Join Date: Aug 2010
Posts: 9,037
Default Re: Why running rich?

are they carburated?
__________________
Truck: 2000 Ford Ranger XLT 4.0 4x4 ext cab
My Build Thread
Mod Ideas
Don't Forget to:
Create a Signature
Show your system

Mods: Brush guard|Front Hitch|Expo Roof Rack|Train Horn|Door/Dash/step/Hood Leds|2" lift|Rear Tow Points|On-Board Air System| 22" & 40" LED bar|and More!
Reply With Quote
  #6  
Old 11-21-2012, 06:45 PM
Learning to use the forums
 
Join Date: Nov 2012
Posts: 12
Default

Nope. Injected. It also burns oil and it misses.. Changed the cap roter plugs and wires.
Reply With Quote
  #7  
Old 11-21-2012, 06:51 PM
Commander Sparkles
 
Join Date: Aug 2010
Posts: 9,037
Default Re: Why running rich?

Quote:
Originally Posted by CAPTIAN KODSKI View Post
Nope. Injected. It also burns oil and it misses.. Changed the cap roter plugs and wires.
what did the plugs look like?
__________________
Truck: 2000 Ford Ranger XLT 4.0 4x4 ext cab
My Build Thread
Mod Ideas
Don't Forget to:
Create a Signature
Show your system

Mods: Brush guard|Front Hitch|Expo Roof Rack|Train Horn|Door/Dash/step/Hood Leds|2" lift|Rear Tow Points|On-Board Air System| 22" & 40" LED bar|and More!
Reply With Quote
  #8  
Old 11-21-2012, 10:14 PM
Sub74
 
Join Date: Mar 2012
Posts: 480
Default

They were a little fouled (black) but not horrible

By the way mine is a STX too

Due to other problems it is almost all new...
Injectors
Computer
Both fuel pumps
TFI
Cap
Plugs
Rotor
Fuel press reg.
IAC
Inlet air temp sensor
Crank turned 20 under with correct bearings
New timing chain
New oil pump
After market oil pressure gauge
Headers
Port matched the intakes to each other and to the heads

Ran really rich before all this was done and the oil press was about 10psi when it was warm, 40-50 psi when it is first started cold

Now it runs much better but it still runs rich and the oil pressure still sucks at 15 psi when it is warm

I obviously really like this truck but it is frustrating me to death

I'm looking for a cheap 302 I can rebuild

----------

Oh couple more things

All the cylinders test at 130 psi except #4 which tests at 100 psi

It burns oil too, did before u did all the work and still does. (I suspect #4 is the reason for that)

It has 40 psi fuel pressure

Does not throw any codes to the tester either KOEO or KOER

I have messed with this thing so much over the past two years I can quote the Chiltons & Hanes manuals both

I have done it so many times I can pull the motor in about 2-3 hours & put it back in 3-4 hours
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #9  
Old 11-22-2012, 05:45 AM
Commander Sparkles
 
Join Date: Aug 2010
Posts: 9,037
Default

I would guess head gasket or rings for the oil but I don't think I have ever heard of them causing a vehicle to run rich but possible I guess

sent from my IPod using the FRF app
__________________
Truck: 2000 Ford Ranger XLT 4.0 4x4 ext cab
My Build Thread
Mod Ideas
Don't Forget to:
Create a Signature
Show your system

Mods: Brush guard|Front Hitch|Expo Roof Rack|Train Horn|Door/Dash/step/Hood Leds|2" lift|Rear Tow Points|On-Board Air System| 22" & 40" LED bar|and More!
Reply With Quote
  #10  
Old 11-22-2012, 06:23 AM
STX RANGER
 
Join Date: Apr 2012
Posts: 94
Default

I have the same problem with my 88 ranger stx I thought it would be the o2 sender. But I haven't found out yet can't even keep the rear window open..
__________________
88 ford ranger stx highrider 4x4 2.9 on 31s 3.73 ratio
Reply With Quote
  #11  
Old 11-22-2012, 08:17 AM
Sub74
 
Join Date: Mar 2012
Posts: 480
Default

I was going to replace the O2 sender because it made sense that it could cause the problem

But then we come back to the no codes

Replacing it is a pure guess
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #12  
Old 11-22-2012, 08:19 AM
STX RANGER
 
Join Date: Apr 2012
Posts: 94
Default

Yeah that's what I'm thinking bc I'm not getting any codes either but its worth a shot.
__________________
88 ford ranger stx highrider 4x4 2.9 on 31s 3.73 ratio
Reply With Quote
  #13  
Old 11-22-2012, 09:00 AM
Learning to use the forums
 
Join Date: Nov 2012
Posts: 12
Default

Sub74; did you have to put a lift on your 88 to fit those 33s? I have 30s with 2inch spacers and I couldn't fit 31s.

----------

And how does your truck do with the 33s? I've been very hesitant to do it cuz I think imma lose a lot of power and over work my tranny. I have 294xxx on the engine and tranny.

----------

Eh the plugs where bad. All the guts stuck to the spark plug.

And I'm also having trouble with some electrical, my tack is 1000rpms off.. So when it's idling its a 1000rpm under 100.. So in other case when idling it doesn't even reach 100 Rpms.

----------

So when I'm at a 1000rpms on my tack I'm really at 2000rpms
Reply With Quote
  #14  
Old 11-22-2012, 09:51 AM
Sub74
 
Join Date: Mar 2012
Posts: 480
Default

I have a 4" long travel super lift soft ride suspension with new springs

It is a great set-up but it was so soft I had to fab a sway bar on the front. (taken from an exploder)

I also replaced the axles a 8.8 in the back and a Dana 35 in the front

I used stock wheels with 33x10.5x33 BFG tires, works great. If the tires where 12.5's then it probably wouldn't work as well.

I attached a picture so you could see what it looked like

As far as your tach problem I would look at replacing the TFI on the distributor, I'm pretty sure that is where the tach gets its signal
Attached Images
File Type: jpg image-989066230.jpg (65.1 KB, 55 views)
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #15  
Old 11-22-2012, 10:52 AM
Sub74
 
Join Date: Mar 2012
Posts: 480
Default

By the way mine has 243,xxx miles on it.

The 33's are not horrible but yes it has to work harder because of them, the axles have 3.73 gears in them

I installed a 4.0 clutch and flywheel on the 2.9 because I knew I would be working it hard, the clutch works great

I cannot use 5th gear because at 70 in 5th it has about 1600 rpm, in 4th at 70 it is a constant 2500 rpm but still lugs down on even small hills

Someday (after I win the lottery I plan on installing 4.56 gears
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
running veryyy rich greenmachine05 4-Cylinder Tech 0 04-26-2012 09:28 PM
running rich and a little miss 912.3l 4-Cylinder Tech 5 02-17-2012 07:20 AM
97 ranger running rich in gas apolloprince 4-Cylinder Tech 1 02-06-2012 04:55 PM
running rich joker515 3.0 Vulcan Tech 0 02-26-2011 10:10 PM
3.0 running rich SmokeyMcPot420 3.0 Vulcan Tech 11 10-30-2009 09:46 PM



Search Engine Friendly URLs by vBSEO 3.6.0 ©2011, Crawlability, Inc.