Fuel issues

[19Walt93]

I've always cleaned combustion chambers by slowly trickling water or Ford combustion cleaner into the carb or air intake with the engine running at 3000 rpms or so. Slowly being the key word. Is it safe to assuming you aren't running it on gas that sat as long as the truck did? Gas ain't like wine, it doesn't improve with age.

 

[1986RangerXL]

Update time: Yeah all the gas in the tank is fresh since the gas tank wasn't installed when I got the truck. Pulled the ECT sensor from the ol Lima we have for parts, as well as put the new radiator in. Got hot first time round the block- needed more coolant, that and seafoam in the intake and it seems to run okay now. Will keep driving it and see how it acts

 

[1986RangerXL]

Don't want to make a new thread so posting this here. The truck idles and runs better, but the idle is still a bit rough and I can feel it misfire while driving.
List of things that have been done:
ECT sensor switched out
Cleaned IAC valve (the shaft spins)
Ran two cans of seafoam through gas tank, one spray can through intake
Checked FPR for leak, and checked fuel pressure
New plugs, wire, and checked coil pack
New distributor

When the plugs were replaced some were pretty nasty, I'm thinking fuel injectors. Problem is it's not a consistent miss. Thoughts?

Really frustrated w this and don't have the $ the throw a $200 set of injectors in and have that not be the problem

 

[RonD]

Did the spark plugs show signs of oil?
Blackish tips

Could be leaking valve guide seals, oil runs down intake valve stem and is sucked in with air fuel mix

You can reduce this with clean and working PCV system, it should create a slight negative pressure in the crankcase and valve covers to reduce the amount of oil going down the valve stems, BUT, the intake Vacuum at idle is very high, 18-21" so hard to overcome when the seals are worn out

You can change valve guide seals without pulling the heads but does take time, not money just time to do all 12 seals

 

[1986RangerXL]

I think they were a little black. Would you recommend maybe a cheap set of remanufactured injectors to try first? Or just go ahead and check those seals?

 

[RonD]

I would check MPG first, leaky injectors will use ALOT of fuel at 30psi fuel pressure, also dirty spark plug for that/those injectors

Clogged injectors will cause Lean condition and pinging/knocking when accelerating

Also a way to test for worn valve guide seals is to drive up a hill and then when going DOWN the hill shift into a lower gear to use the engine as a brake to slow you down, this increases the vacuum in the intake above 30", so if seals are worn more oil would be sucked in
Then at the bottom of the hill step on the gas and watch the rear view mirror for a puff of Blue/black smoke as most of the leaked oil is burned all at once
Bad rings can also cause this, but valve guide seals are more likely

 

[1986RangerXL]

I would check MPG first, leaky injectors will use ALOT of fuel at 30psi fuel pressure, also dirty spark plug for that/those injectors

Clogged injectors will cause Lean condition and pinging/knocking when accelerating

Also a way to test for worn valve guide seals is to drive up a hill and then when going DOWN the hill shift into a lower gear to use the engine as a brake to slow you down, this increases the vacuum in the intake above 30", so if seals are worn more oil would be sucked in
Then at the bottom of the hill step on the gas and watch the rear view mirror for a puff of Blue/black smoke as most of the leaked oil is burned all at once
Bad rings can also cause this, but valve guide seals are more likely

So far it has gone through almost half a tank of gas just running around the block and idling in driveway. Dirty spark plugs as well. The exhaust has a thin white smoke, not blue or black. Going to try a $90 set of injectors I found, if that fixes it I will eventually put Bosch injectors in

 

[PetroleumJunkie412]

So, before you do, get a can of Liqui Moly Jectron and Intake Valve Cleaner.

Most fuel system cleaners do not work. I've completely discontinued the use of seafoam as well.

Jectron and IVC by Liqui Moly (amazon btw) are the only two cleaners I've found that actually do anything, along with CRC's intake cleaner. I'm guessing seafoam was reformulated.

If you need injectors, I could probably be convinced to clean up a set for you - I have a few sets of Merkur Scorpio and Ranger 14lb ones here, and don't need them.

 

[1986RangerXL]

@PetroleumJunkie412 Thanks for the suggestion. I'm still leaning towards new fuel injectors, the motor has 158,000 on it and I have reason to believe they were never changed. This is going to be a DD so the peace of mind would be great. Also kind of in a rush to get this done since I'm going to take a job at a local farm. If we get more snow, my little v6 Mustang is not making it out there lol

I will PM about the injectors

 

[RonD]

Well my 4.0l with 400k still has factory injectors, and MPG has changed in the 10+ years I have owned it, but did I did put in New O2s at 300k

 

[1986RangerXL]

Fuel injectors on the way. Was doing my weekly start up routine when I noticed something. The truck idles rougher under electrical load (headlights.) It is noticeably smoother with them off (although still the occasional stumble)

I pulled the TPS while it was running to see if it would run better. Not sure if this is the correct way to test, but the idle speed was a lot better. Drove it a bit and tried hard to make it miss, still misses every once and a while but not undrivable. Want to try fuel injectors before I order a new TPS

 

[Shran]

Might be worth replacing the negative battery cable or at least checking it over really well for corrosion, and having the alternator tested. We had another thread here recently about AC voltage leaking out of the alternator and causing weird problems, something to check anyway.

 

[1986RangerXL]

Might be worth replacing the negative battery cable or at least checking it over really well for corrosion, and having the alternator tested. We had another thread here recently about AC voltage leaking out of the alternator and causing weird problems, something to check anyway.

Right, we've already swapped the negative cable with a better one from parts truck, and the alternator was rebuilt due to charging issues.

Injectors going in this weekend and new TPS sensor, hopefully that's the end of that..

 

[Shran]

My bad, I must have missed that part.

 

[Josh B]

Something we've all overlooked, myself included until not so very long ago, is while trying to get the ground working sufficiently pull the anchor bolt through the starter(the same one it's anchored to yep) and brush the bottom side of it also