Friends,

I have a 97 Ranger - 5spd - with 220k. I bought the truck for $250, and have been getting it back in shape. I was intending on turning it into an Electric truck, but with just a rough idle seemed like it was worth fixing. It would drive ok, but stall coasting to idle..

I bought it with no CAT, it's been replaced with a straight pipe.

Things done:
Fuel filter - $6
Replaced plugs and wires - $40
Replaced broken front springs - $85
Found that 2 vacuum hoses near IAC were cut?!?! repaired
Replaced nose and replaced bumper. It now sits and looks better. $250
Steering pump and hoses - $100
A bottle of Heet - $1
IAC - cleaned / then replaced $40 - Greatly reduced likelihood of stalling - reset idle screw
Seafoamed a few weeks ago - no major effect except smokescreen - that night, idled for an hour! without stalling - after nose was back on, trip up and down street, (1 mile) and stalls rolling into drive @ idle....arggg!
TPS - tests ok .96 to 4+V @ WOT

Codes thrown
P1506 - IAC - idle screw still seems pretty far in

Most recent excitement:
With rough idle continuing, pulled throttle body after testing TPS. Cleaned thoroughly (hard to remove buildup, but berryman's cleaned it up)
cleaned pcv (still rattles)
Cleaned MAF with MAF cleaner.
All back together, and started for about 10 seconds, and then stalled, Stalls became misses, misses became cranking without even a firing
Pulled the positive wire and called it a night

Put the charger to work, and pulled the passenger bank sparkplugs tonight and they were fuel fouled.
Cleaned, reinstalled and cranked without success.
Still no codes...

I'm losing hope on my great 'deal'

I also promise to close the thread out with a solution, or a craigslist ad.

Please help!!! TIA!

 

Update..... Guess what..... make sure you're not going to clean the MAF right before you're going to run out of gas........ DOH! I added some gas and 3 or 4 ignition turns, I could hear the fuel pump 'load up'. I turned the ignition onand she started right up...... Too bad the stalling continues.
Please help!!

 

Stalling: Could be a vaccuum leak (spray carb cleaner around and note idle changes), bad fuel pressure regulator (not sure if 97's FPR is on the fuel rail, if it is- pull the vaccuum line off and see/smell for fuel=bad FPR - too much fuel pressure). Try pulling the vaccuum line off the EGR valve, plug the line and check for stalling = sticky EGR valve not closing. Try running it with the MAF disconnected.

Disconnect the IAC while it is idling, note change in idle = good IAC, no change = bad (yes, I know you replaced it). How much carbon was in the IAC port?

Make sure the intake tubing from MAF to TB is not leaking (carb cleaner again).

Are you following a manual's procedure when adjusting the idle screw?

Might do a compression check....

I'm sure somebody has more ideas. I think you're gonna fix it real soon.

 

Thanks for the suggestions. I have done extensive vacuum link spray testing to no avail. Initally had a leak. The 2 red ones by the EGR were cut....(who knows why...gotta love buying a project)
The IAC testing works as expected. I don't have a tach to get the 550 RPM without the IAC, but I get it down to stalling, plug the IAC back in and it smooths right out. Idle has a tendency to degrade
This PCV was cleaned and rattled real good. Hose looks good too. I'll pull the egr vacuum hose and plug it.......
Intake tubing was missing a clamp previously and replaced it with a pipe clamp
If I pull the MAF. The thing dies and doesn't want to run (Limp mode doesn't seem to work)
My buddy offered up his Aerostar MAF (Same) as a test, but I haven't had time to borrow it...
I did look at the fuel rail pressure regulator hose... no gas or smell, but I'm now leaning that way.... I have a GM fuel pressure tool, but the schraeder is the wrong size.
Gotta call for a loaner.

Also.....I promise to close out this thread properly. If this thing ever gets fixed, I'll document and support the thread after the fix to help others in this same boat.... It seems that there's a lot of this 'problem' out there and you never see a resolution. Kinda annoying as a Shade Tree guy.....

 

You should also investigate the timing belt and tensioner .Belt may be old / stretched or the tensioner may be frozen leaving too much slack in the belt. This would cause valve timing issues creating idle problems.

 

Friends,

Another update. I bought a fuel pressure tester @ Harbor Freight for on $10! The pressure came out @ 37psi and rock steady! 20-40 is good... according to the tech files..

I'll check out the timing belt now, would a stretched belt make it idle ok, but also degrade after 10 secoonds too?

 

bump - any other suggestions??

 

Not that i expect this to fix your problem.
But, reset the KAM. Always a nice thing to do on a vehicle you dont know much about.


Also, make sure you EGR is not on while engine is at idle.

 

Throughout the process, I've been doing KAM and OBDII scanner resets... I haven't done the hardcore 10 mile driving, I've just been driving up and down my dead-end street (half mile round trip). Do I need to do the 10 miles of regular driving before it really relearns?

 

Pull the inspection cover and recheck the alignment marks for the timing belt.If it was or even wasn't replaced before you got it , it sounds like it may a tooth or two off.

 

Just wanted to provide an update.... What I found was that the previous owner totally booger'd up the timing and got it totally wrong. I followed the Factory manuals (much better in explaining the timing marks (Big note: the timing mark is not the depression around the gear flange. The correct mark is a diamond / triangle that's stamped thin the flange. It's hard to see, but take your time)

 

so is all good now?

 

j

 

Still stalling - Check the valve lash , cylinder leakdown test for burnt valve.
Warm hard start - fan clutch OK ? Leaking injector (smell raw fuel in exaust when starting)

 

any word lemon? i have a 93 thats doin the same sorta thing, rough idle but when i drive it runs great, stop at a light and it runs roung again, give it gas and shes all good wtf?! lol

 

Still having the same problems. It's still a project and not a driver yet. It did throw a code, I found a P1506 today, but other than that still no improvement. No fuel smell on a hot start, but it is acting like it's a leaking injector. Give it 5 minutes and it starts right back up.

I'm going to do a compression test for good measure.

Anyone want to comment on solutions to the P1506?