Ok, so I will try to keep this short. It failed emissions and has a very rough idle. When you drive, it feels like it is only running on 3cyl. If I try to operate the throttle with your hand it makes noise that I can only describe as too much air (kind of a reverse muffler sound) going in.
1988 Ranger XLT, Supercab, 2.3L, 5sp, 4x2, 121k

Old thread:
https://www.ford-trucks.com/forums/s...d.php?t=410957

Just replaced the following with Motorcraft parts:
Plugs
Wires
Cap & rotor
Coil

So after this "tune-up" it still runs the same, so I checked the fuel pressure. Stupid Ford puts the valve under the intake on the 2.3L where you have to remove several things just to get to it. Anyway, I only got 25-30psi with the key on and engine off (supposed to be around 40psi with the engine off). The 3 things I could think of that might be a problem:

1) fuel filter (it is less than 2yrs old)
2) low pressure in tank pump (I replaced the tank 1yr ago and didn't replace the pump since the fuel pressure was good)
3) high pressure pump on the frame (never touched it)

I think I hear both come on but I need to get someone else to help me while I am under there to be sure. Any opinions or suggestions?

 

Well might as well replace the filter anyways. From what I hear, to check the HP pump, you can put a 2 liter bottle of gas at the end of a fuel line running to the HP pump and see if it will pull gas from it. Be careful. 25-30 is out of the range of the low pressure pump though. So I am willing to bet the HP pump is still good, maybe going though.
Go ahead and replace the fuel filter, it won't hurt anyways. Did you check the O2 sensors?

 

What were the emmision numbers/ failure?

The in-tank pump only has a volume requirement that you can check, if your manual dosen't list it let me know and I dig it up, I know I have it someplace.

 

I should have mentioned that, yea I am going to replace the fuel filter anyway just to be safe. When I bought the truck the previous owner had the oil changed at Jiffy Lube + filter ~2yrs ago.

I should have also mentioned (if it is important) that once the line was pressurized and the gauge was reading ~30psi I hit the pressure release button and got very little fuel into the overflow container. Also, is it supposed to re-pressurize as long as the key is still on? It didn't for me.

I guess I should have posted the emissions results too......... my bad. I am not too good at interpreting these results, so any input would be helpful.

The test showed the following:
......................15mph
............Limit......Reading....Result
HC ppm...179.......354..........Fail
CO%.......1.52......0.68........Pass
NO ppm...1227......169.........Pass
___________________________
RPM.........2925..................Valid
Dilution.....14.3...................Valid

.......................25mph
.............Limit......Reading....Result
HC ppm....174........489.........Fail
CO%........1.96.......1.04....... Pass
NO ppm....1121.......436........Pass
___________________________
RPM.........2852....................Valid
Dilution......14.1...................Valid

Visable Smoke Inspection.......Pass

 

The HC is high; this implies too much fuel/unburnt fuel. This could be consistent with a weak/dead cylinder. It seems that you've ruled out ignition problems judging from your list of replacement items. If it wern't for the noise you noted (and that I don't fully understand but I do have a guess) I would have suggested that you next check timing and carb adjustment. However, in this case, I would do a compression test and prey that it's not low compression on just one cylinder for whatever reason. If that sound you describe is what I think it is, it could suggest a burnt valve. A compression test will prove/disprove this.

 

CB9M has a good place to start....the system will not build pressure again, when you first turn the key on it's on a timer.

 

Something else to check on the fuel pressure: the hose that goes between the in tank pump and the outlet inside the tank. Mine was melted when I got the truck. Probably due to additives. It had good pressure in the driveway but went low as I drove it. I pulled the bed and replaced it from the top. Then started working on the other issues. and still am...
Rich

 

Ken, sorry to ask what might be a stupid question....... (I have been dealing with a lot lately), but what is "CB9M"?

 

CowboyBill9Mile is CB9M I do believe.

Not a stupid question, when I first saw CB9M I was like "oh great must be some other technical term to learn..."

 

RangerPilot - You are probably right. I am a bit overstressed right now with the sudden death of my cat (Geordie) I wouldn't have put that together.

It does seem funny that this would happen after sitting for a while (I didn't really drive it over the summer, AC doesn't work). I will have to see if I can dig up a compression tester. BTW it is fuel injected, no carb.

The sound that is hard to describe is kind of a delayed reaction to hitting the gas. When I open the TB up a bit the engine is slow to respond, and makes a deep "inhale" like popping sound until the RPMs catch up.

So would it even run or be rich if there is not enough fuel pressure. According to the manual I am ~10+psi low.

 

How long has it been sitting? Could you just be having a problem with old/stale gas in the tank?

I don't see that you posted your O2 and CO2 values from your smog check. You might be suffering from a lean misfire. Any vacuum leaks?

 

LOL, you are correct, sorry about that guys.

 

It was only sitting over the summer (2-3mo). And the tank has been filled since then.

The #s I posted were all that was listed on my report.

There are no vac leaks that I know of. About 1+yr ago I replaced most all of the rubber hoses under the hood. I have a pic of the old plugs if it would be useful.

 

Did you try a compression test like CB9M said, you need to get to reason why "it feels like it's running on 3cyl". If it really is that would explain the high HC.

 

Ken00 - No, I have not been able to yet. I can't find my compression tester, so I may have to go buy one again. After I finish dealing with some family tragedies and a sinus infection I might be able to get this done.