Another thirsty, low power Ranger

[Jaydub]

Hi, My apologies if I'm repeating previously answered questions but I spent most of last night reading through old posts and I'm still confused. Also, because I'm in England I can't just nip out to Peps(?) to swap out a part...
So...'88 Ranger, 2.9 V6, 2wd, auto', bloody good nick, 125000 miles - one of only a handful in this country.
Never had a problem previously, always starts and runs as it should.
Driving home yesterday, severe power loss, trailing a huge black cloud of unburnt fuel. Twenty seconds or so later, cleared its throat and ran clean. A few miles on same story again. Parked up on the drive in Park or Neutral, revved it and it laid down a huge black cloud again, fifteen or twenty seconds later it ran clean. Exhaust is as to be expected, thick black soot. Fuel consumption was around six or seven - I normally get about twenty.
Following advice previously posted on here I checked the vacuum pipe from the FPR (fuel pressure regulator), there was no sign of any fuel leakage into it but it was loose and leaking. I've sorted this.
I fired it up and it started same as always and settled down to a good idle/tickover and did not smoke. Could this leak have been responsible? I'm wary of driving it as I can't afford to damage the cat' or is it too late to worry about that? I've seen in previous posts that it may be the fuel regulator (FPR), O2 sensor, or one of the other sensors - are there any ways to check without specialist kit?
I'm not a total novice - I've rebuilt Harleys, chop's, old Brit' sports cars and hot rods but I'm really a carb's and points man (this is my modern daily) - if this was one of my other vehicles it would probably point to something simple like flooding/float sticking or similar...I've been through the Haynes manual and it was little help pointing to "a fuel or electrical fault" - I'd worked out that much. It states how to remove and install various stuff like the AIT, PCV and MAF but I'm struggling to work out what any of them do...
Also, any replies please keep jargon/abbreviations to a minimum as we really are two nations divided by a common language. Many thanks...

 

[blh0007]

Hey Man,
the loss of power could lead to a compression problem and the black smoke means that you probably have oil getting into your combustion chambers which also can be connected to a compression problem. there could be a number of causes for this. check the compression on all of your cylinders before going to the next step... i am not sure what the compression should be for your engine, but just make sure that it is consistent on all 6 cylinders.

 

[Mike828]

Did you pull codes?

http://www.therangerstation.com/tech_library/OBD_I.html

 

[Jaydub]

Until you posted that link I hadn't realised you could pull the codes without specialist kit...so much information on here hadn't found that. Thanks.

 

[Big Jim M]

The answer is YES! Black smoke is rich fuel mixture... BLUE or WHITE smoke may mean oil burning.. The lack of a tight fit at the vacuum port can lead to a rich condition.. Go ahead and drive it I betcha you have repaired the problem.
Big JIm

 

[Jaydub]

Sorry I haven't been back sooner on this but I didn't want to waste anyone's time and have been trying a few things before claiming success or crying for help.
First time out after fixing vacuum leak truck drove great for first fifteen miles or so then it was back to misbehaving again.

Tried to pull codes using the info in the link above (as per "Check engine" light). Unable to pull codes. Heard a loud pop from passenger footwell - definitely not a relay - but couldn't see any damage. Pretty certain that I followed instructions and sure that I did not short anything.
Couldn't find any blown fuses, burnt wiring or similar.
Took truck out for a ten mile run today - misbehaved same as before but no other problems - "Check engine" light came on for a minute or so but went out again.
Made up a test lamp and tried to pull codes again...
Key out, ignition off - test light lit.
Key in, ignition on - test light goes out and stays out.
Key in, engine running - test light stays out.
Any ideas, is this all part of the original problem or have I created a new one, or...am I just being dim?

 

[low-keys89v6]

Sounds like its dumping fuel for whatever reason. The (1 or all 6) injectors would have to be staying open for this to happen or your losing spark momentarily and when it fires again its way to rich. Knowing if there were any CELs present would help. I bet the check engine light is for a miss fire...duhh right. lol.

BIG JIM...do you think its possible the injectors are sticking open or more of a faulty ignition coil? Just a thought. Im sure it could be a computer issue also. I was just thinking if it was a compression issue it would not "clear" its self.

Feel free to tell me to shut up if im not helping here...lmao

 

[bobbywalter]

put a vac gauge on it. see where its at and what its doing...maybe a valve is bad or the intake has a huge leak or something....

what do the plugs look like?


what is the fuel pressure doing under load and when this is occuring?


almost sounds like the map is getting erratic vacuum due to a bad hose or the wiring is damaged or the map sensor itself is failing or failed. the vac gauge may help find the leak if there is one or indicate a physical problem with the engine that is causing the map to piss the engine off due to the bad signals its getting from the engine issues.

 

[Jaydub]

Just thought you might like to know the outcome, or the outcome so far...
Still unable to pull codes, don't know why. Check engine light is out and staying out. - good!
Finally tracked down a vacuum leak (you guessed it) from the servo/brake booster. Just put it back together and went for a drive - I'd forgotten how well it went and how nice it could be to drive - must have been getting worse for a long time. So I'm keeping my fingers crossed that it 's sorted. I still need to pick up a couple of spares to make the repair permanent but it looks like job done. Thanks for pointing me in the right direction. P.S. British car spares shops look at you strange when you enquire if they've got a such and such for a first gen' Ranger - don't think they get asked very often...Cheers guys.

 

[robertc1024]

That's good you got it fixed and by the way, parts shop guys look at you funny if you ask for a whitworth threaded bolt or a needle for your SU carbs.