Open the throttle today for the heck of it and took a look inside the throttle body; found a monster. Kind of looks like an oil leak under the chasis full of dirt and junk. Completely black and oily. Cleaned out the IAC and EGR. Ran like crap for a while until the computer got up to speed on the changes. Idle speed was up. I expected this, because I've had to turn it up just a little annually for the last 5 years. Ran it in town and on the highway. Adjusted the idle speed down.

I'm thinking Sea Foam would be easy for cleaning the throttle body and intake, but I'm not sure I want to flush all that crap through the engine. Or if it will even come off without scrubbing. Would I be opening a can of worms if I take off the intake manifold? Never done it. What kind of trouble can I run into? Funny thing is that there's a sticker on the throttle body that says "Do not clean inside throttle body or adjust idle screw in the CCW direction".

 

Should have mentioned I'm running a 94 2.3L 5speed 2wd with 215k

 

I'd run the sea foam in your oil and suck it through your intake and your fuel that would clean it. i have heard of it knocking carbon loose and bending a valve but i doubt that happens all that often it would be good for your motor to get cleaned

 

Been told by a mechanic/friend that the reason for the sticker is that there is a coating on the throttle body. Most cleaners will take this coating off.

 

Its there for a reason! Do not remove it. It is only before the butterfly correct?

 

3M TB cleaner claims to be coating safe but I usually soak it down with Deep Creep and gently scrub with soft bristle brush - doesn't seem to hurt the coating as far as I can tell.

 

if its oily, its probably motor oil coming in from the pcv valve (the tube that runs from your valve cover into the intake tube).

They make oil accumilators that will collect the oil, keeping it out of the intake system.

 

i got after mine with a little carb cleaner, didnt feel any different, nor has it thrown codes or decreased MPGs.

 

Yeah, it gets pretty nasty in there.

 

The sticker is on the throttle body before the butterfly. It's actually pretty clean at that point. Open the butterfly and immediately on the other side of it is carbon and oil. Just like someone spray painted it on every bit of surface area in there. I can imagine it's like that through the whole intake. I've been running Sea Foam in the gas tank for several years, but never ran it through the throttle body. The IAC had a good amount of carbon build up and the EGR has a lot of carbon and oil in it. Sprayed some Sea Foam in both and put them back on yesterday. Didn't clean the throttle body or intake yet. Just wanted to get some advise to see what the best thing was to do.

After cleaning the IAC and EGR yesterday I have been having some random idle problems. Ocassionally the idle will drop real low almost to where it will stall. Does this once in a while whether it's cold or hot. Seems completely random.

 

SEAFOAM AEROSOL by Seafoam - Part SS14 - Advance Auto Parts

 

Scrubbed the throttle plate with a tooth brush and wiped out the area as far as I could reach in there. Spayed a little Deep Creep in there to flush out what loose carbon there was. Did not want to dump a bunch in there and have it all go through the engine at once. Like I said there is a lot of carbon. After cleaning the throttle plate it is a little more responsive when you step on the accelerator. Still getting random idle problem though. Sometimes high, sometimes low. I suspect the IAC is bad since it started right after I cleaned it.

 

PB Blaster LMT is a good cleaner too. Just spray a few ounces and let it soak for a while. Stuff will scrub right off with a tooth brush and not damage whatever coating is on the TB blade.

 

If anyone is following this I have not had time, nor will I have time in the next week or so to get at the idle problem. I did find some writing that says if you adjust the idle screw at all you may have to adjust the throttle position sensor. If the two are not right in relation to one another, it can cause all sorts of problems. This is what I'll look into next since I had been adjusting that idle screw a lot.
The Ford Ranger Throttle Position Sensor

 

I"m not sure I follow that. The TPS is not in itself adjustable. The only way to "adj" it would be to slot the mounting holes. Do people actually do this????

*I see what you are saying about the the two not correlating correctly, but I wouldn't want to do anything but turn the idle screw back?

**Sorry this post is of no help, lol. just curious

 

Yes people actually do that. There is actually enough play in the factory mounting to get some small adjustment out of it. I don't know how it is with the Ranger's TPS but I did make such an adjustment when I put a different TB on my F-150.

 

Had a chance to look at the TPS today. Hane's manual says it can't be adjusted. All tests were good. Did find a little corrosion on the connections. Cleaned them up and I'll see how it idles tomorrow. Did notice at normal temp that it idles up and down ever so slightly about every 5 seconds.

 

Don't believe everything you read.

 

Still have same problem. Idle is not consistent. Drops pretty low sometimes. Flexed all vac hoses, wiggled all connectors, rapped on various components and did not have a change in idle. Still does not have high idle when cold. Stalls or darn near stalls after a several minutes of warm up. Start it up and it's fine other than real low idle once in a while.

 

Have you hooked up a scan tool to see what the MAF voltage is doing? The MAF and the TPS have to be in sync with each other, if one is not getting or sending the correct reading then you'll have idle/driveability problems.

 

What do you mean by scan tool? No problems while driving, everything seems normal. Just has an inconsistent idle. The first problem that I still have is that during the cold Wisconsin winter it only stays in high idle for maybe 30 seconds max. It will idle at normal speed for about 5 minutes and then stall. Start it up and it runs great afterward. I cleaned the IAC, EGR, and throttle body/plate just recently hoping it would fix the problem. Now I have an inconsistant idle(rpm's drop), that is happening all the time, along with the winter idle problem. I suspect the problems are related. Could be that I screwed up the IAC by cleaning it. That is my number one suspect. I cannot figure out any pattern to the inconsistency. Considered air temp, engine temp, angle the truck is sitting at, humidity. Haven't had time to do real thorough testing. Should have plenty of time in a couple weeks.

 

Scan tool is something you plug into the OBD port to see trouble codes and monitor data channels from the engine, transmission, and emissions stuff. MAF and TPS voltage should be fairly consistent and if you see one fluctuating while the other isn't that could give you another indication as to what's causing the problem.

 

Well, I think I figured out the idle problem. Did a brake job and wheel bearings today. Went to start it and no fuel pressure. Fuel pump is not running. Hopefully the idle problem will be fixed by replacing the fuel pump. Keeping my fingers crossed.

 

Pushed the impact switch and it seems fine. Wiggled fuse and it looks good. Swapped fuel pump relay with another and it still doesn't start. Pulled fuse and switch and continuetly is good. wiggled wiring in engine compartment. Started up fine. Could not recreate the problem. Since it's running again it still has the random low idle problem.

 

Cleaned the MAF again even though it looked spotless. Wasn't to long ago that I cleaned it. Idle increased significantly after cleaning. Turned the idle screw down. Still have random low idle problem. Stopped pointing down hill today and the idle dropped so low it almost stalled. Never dropped that low before.