MAF sensor problem

[Currency]

Another day another problem.

Here we go and I'm just posting this to help everyone out hopefully and figure out one more issue I have.

I removed the black plastic tube from the intake on my 1994 explorer. I was checking out the MAF sensor to make sure it was not extremely dirty. Well it was cleaner then you could really ask for. But the intake tube I guess you would call it has oil in it, You can smell it and touch it to see that it's oil. I don't know where this would be coming from but if it's there my explorer should be inhaling oil now

Where could this oil be coming from?
Also should it be something that should be fixed asap?

My truck doesn't use oil that I've noticed so it's just another bugger for me.

Also I topped off my radiator even though I plan on flushing it tomorrow, It was slightly low.

While she was running I noticed the annoying missing or cutting out she does every time I start her, warm or cold. So I unplugged the MAF sensor and wow it doesn't do it anymore.

Is it ok to drive with that unplugged? I have to replace my RA brackets soon and buy another set of bushing. Money is tight that's why I am asking. I noticed the check engine light comes on about as soon as I start it now but it runs a lot better then it ever has. I thought it was the fuel filter but I guess I was wrong

I have some more questions about radius arms and alignment messing up but I'll save that for another day. I've already put older tires up front and put my new ones in storage until it's fixed.

Let me know what you guys think.

 

[doonze]

You can run without the MAF, it will run in "closed loop" mode...think not the best for the enviroment or MPG, but it will run.... it'll be a dog and throttle response will be lacking but it will run. Just clean it and see what you get, even if it LOOKS clean.

Also, it's possiable unplugging the MAF may send other sensors into "closed loop" and even though unplugging the MAF fixed your issue, it might not be caused by the MAF at all. I have been unable to get a hold of a OBD 1 Ford PCM design team member to find out for sure what all it does when the MAF is unpugged... LOL

Also yes, it will keep your CEL solid until you plug it back in.

Look at your black intake tube... See that flexy rubber tube that attached to the hard plactic one right after the MAF?? It's about 1" around.... it goes over to your oil filler tube on the valve cover.... and that's where the oil is coming from.

EDIT:
If you go to my sticky thread in my sig below about the Radiator flush, and go to my pic of the engine bay where I show where to unscrew the intake tube, I have the hose I'm talking about circled...

 

[2000StreetRod]

MAF Disconnected

. . .

But the intake tube I guess you would call it has oil in it, You can smell it and touch it to see that it's oil. I don't know where this would be coming from but if it's there my explorer should be inhaling oil now. Where could this oil be coming from? Also should it be something that should be fixed asap?

. . . While she was running I noticed the annoying missing or cutting out she does every time I start her, warm or cold. So I unplugged the MAF sensor and wow it doesn't do it anymore.

Is it ok to drive with that unplugged?
Let me know what you guys think.

It may run in Park OK without the MAF sensor but I doubt it will do well in Drive. When you disconnect your MAF sensor the PCM reverts to a preset mode. Your performance as well as your gas mileage will suffer. You need to determine why it runs so poorly with the MAF sensor connected and then correct the problem.

I also have a lot of "crud" in my intake tube. I suspect that my PCV valve needs to be replaced.

 

[Currency]

Look at your black intake tube... See that flexy rubber tube that attached to the hard plactic one right after the MAF?? It's about 1" around.... it goes over to your oil filler tube on the valve cover.... and that's where the oil is coming from.

EDIT:
If you go to my sticky thread in my sig below about the Radiator flush, and go to my pic of the engine bay where I show where to unscrew the intake tube, I have the hose I'm talking about circled...

Yeah I seen the tube, Had to unhook it when I pulled the plastic intake piece out to inspect it. It just slid right off. I'll remove it tomorrow and clean it out good, the plastic intake piece I mean.

I've read your post about flushing the radiator. It's well written and appears you have put a lot of time into it.

I test drove it to my fathers house, About a seven minute drive with several stop signs in between. It seemed to run fine but was lacking in throttle response after coming to a near complete stop.Other then that it was all I really noticed.

I'll be heading to a friends house tomorrow. He is a full time farmer and full time junker with a nice new roll back

He has a 2nd gen explorer there and will most likely let me have the MAF sensor and the T/C shift motor for under $20. I figure it's worth the shot because a new MAF sensor is around $100 local and $81 from rock auto.

It's a sport model, Maybe 95 but the tag in the door is MIA. I looked at the transfer case and it appears to be the same. Last time I was out there I cut the strap holding the hood down and it looks about the same as my motor, well MAF seems to be the same. With money being tight I can at least do these things to save some money and make sure it's not the MAF causing the rough idle and start up. It died on me once because of it.

as a bird would say, "That is cheap, cheap cheap" :

 

[Currency]

EDIT:
If you go to my sticky thread in my sig below about the Radiator flush, and go to my pic of the engine bay where I show where to unscrew the intake tube, I have the hose I'm talking about circled...

In you guide to flushing the radiator you mention something about using an air compressor. My father has a large industrial sized one that I have access to

Makes for faster work with air tools instead of hand tools. Do you have more information about using the air to flush the radiator?

Thanks again

 

[doonze]

In you guide to flushing the radiator you mention something about using an air compressor. My father has a large industrial sized one that I have access to

Makes for faster work with air tools instead of hand tools. Do you have more information about using the air to flush the radiator?

Thanks again

I don't, but the idea is you fill up the channels with water, then blow it out with hi pressure air, I understand the idea, just haven't tried in myself, no access to air.....

 

[mhallack]

I got MAF issues too, removed it and ran it briefly. The only difference I noticed was at stop signs it almost sputters to a stop, the engine, and the CEL was on full time. So I out it back on and it's back to acting the way it has been, which is running a bit rough, CEL comes on after 1-3 minutes of driving and occasionally when going into overdrive, will lose power. (I pull over to the side of the road, shut the engine off then start again, seems to temporarily solve the issue) I've cleaned the MAF, no changes, so I'm gonna replace it, I will finally have the money to do this.

Good luck!!

 

[Currency]

I was just thinking about updating this thread.

I've cleaned my MAF with MAF cleaner, Cleaned it's little sensor thing, and cleaned the connectors with contact cleaner.

my issues became somewhat worse. I also believe someone (Tbars, maybe) said even if it runs better with the MAF unplugged it may in fact be something else causing the entire problem.

I just returned home from a local hospital, I'm fine, My sons asleep (waking up now at 5 am ) and my aunt has the flu. While there I went outside for a smoke and started my ex because I'm a puss and got cold. It ran fine for a few minutes after I moved out of the handicap parking space into a normal one.

Then it started it rough idle, 1,500 down to 500 and nearly killing itself. It does this at start up most of the time and is generally fine when it's warmed up. Sometimes it may do it a little until I start moving if I shut if off and then restart it.

So it may in fact be my MAF unit, But I'm thinking maybe TPS also.

Anyone agree with me to some extent?

BTW, My main bearings have not been knocking under load for a few weeks, well since its cooled off outside.

Still getting a motor I located for a spare or backup and while my current motor is fully rebuilt, bored out and the whole nine yards. I'll try to figure out somewhere locally to dyno it once its completed sometime next year

 

[2000StreetRod]

Clean the IAC valve

. . . I've cleaned my MAF with MAF cleaner, Cleaned it's little sensor thing, and cleaned the connectors with contact cleaner.

my issues became somewhat worse. I also believe someone (Tbars, maybe) said even if it runs better with the MAF unplugged it may in fact be something else causing the entire problem. . .
Then it started it rough idle, 1,500 down to 500 and nearly killing itself. It does this at start up most of the time and is generally fine when it's warmed up. Sometimes it may do it a little until I start moving if I shut if off and then restart it.

So it may in fact be my MAF unit, But I'm thinking maybe TPS also.

Anyone agree with me to some extent?

I doubt that it's the MAF sensor or the TPS. Your vehicle drove with the MAF sensor disconnected which means the PCM was relying on the TPS and engine rpm for fuel control.

I suggest that you disconnect the electrical connector to your IAC valve (with ignition Off) and then try and start the engine. If it runs the same as when connected then your IAC valve is not doing its job. Remove it being careful not to lose the gasket, clean it with MAF sensor cleaner or throttle body cleaner and then reinstall and reconnect.

Check all of your vacuum hoses for cracks. A vacuum leak on one bank will make the engine idle unstable.

The hose that connects your main intake tube to the valve cover provides inlet air for the PCV system. Air flows from the main intake tube into the crankcase via the valve cover port. Crankcase fumes exit the crankcase thru the PCV valve and into the intake manifold. The hose you're concerned about shouldn't be any oilier than the inside of your main intake tube unless your PCV valve is clogged.

 

[Currency]

I doubt that it's the MAF sensor or the TPS. Your vehicle drove with the MAF sensor disconnected which means the PCM was relying on the TPS and engine rpm for fuel control.

I suggest that you disconnect the electrical connector to your IAC valve (with ignition Off) and then try and start the engine. If it runs the same as when connected then your IAC valve is not doing its job. Remove it being careful not to lose the gasket, clean it with MAF sensor cleaner or throttle body cleaner and then reinstall and reconnect.

Check all of your vacuum hoses for cracks. A vacuum leak on one bank will make the engine idle unstable.

The hose that connects your main intake tube to the valve cover provides inlet air for the PCV system. Air flows from the main intake tube into the crankcase via the valve cover port. Crankcase fumes exit the crankcase thru the PCV valve and into the intake manifold. The hose you're concerned about shouldn't be any oilier than the inside of your main intake tube unless your PCV valve is clogged.

Thank you, I will attempt to look into all of these things later today. But seeing how I have finals due at 3am my time on Monday (midnight AZ time) I may not be able to get to it until Monday of Tuesday. I'll try to look at it later today if I get these pesky finals done.

Not even had time to start on one yet

 

[Currency]

Whenever I unhooked the IAC it would start but die within seconds. Is this normal?

 

[Potomac30]

oily air intake

I vote for the clogged PCV. If blow-by can't be evacuated from the valve cover through the PCV (vacuum @ intake manifold), then pressure can force the blow-by back through the fresh air intake via the hose hooked from the oil filler to the fresh air intake. Kind of like a stopped up toilet... it's gotta go somewhere.

 

[2000StreetRod]

Normal IAC valve

Whenever I unhooked the IAC it would start but die within seconds. Is this normal?

Yes, most V6 engines won't run without the IAC valve being connected unless the throttle plate stop is adjusted. It sounds like your PCM is able to control the idle speed via the IAC valve (a good thing). The IAC valve is an electro-mechanical device and eventually it's range of control decreases. Cleaning it often helps but not always.

 

[Currency]

I vote for the clogged PCV. If blow-by can't be evacuated from the valve cover through the PCV (vacuum @ intake manifold), then pressure can force the blow-by back through the fresh air intake via the hose hooked from the oil filler to the fresh air intake. Kind of like a stopped up toilet... it's gotta go somewhere.

My father mentioned something about this recently. My plastic intake tube has some oil in it from the blow-by. Then my father went on to inform me my uncle told him to never buy a ford because they have more blow-by problems then chevy does. I don't know if this is true but my uncle was a very smart person when it came to these things. When he past away everyone wanted his 56 chevy including me, but it was auctioned off and his closer family fought over who got how much $$$$$. I would have rather had the car or my uncle then the money.

The IAC valve is an electro-mechanical device and eventually it's range of control decreases. Cleaning it often helps but not always.

I had planned on giving it a good cleaning today using the great write up I had found. You wouldn't believe by googling IAC Valve explorer, the first one on the list is the writeup here on www.explorerforum.com

Thanks everyone for the interesting information, I will clean it today if my son allows me the time and report back here. I have more time then money so it's always worth a try. Maybe my next tank of gas will yield more then 200 miles of city driving

 

[Currency]

I was outside just looking around and preparing to clean my IAC valve and just so happened to open the butterfly on the intake to see what appeared to be a black chunky blub of burnt and dried oil. After removing the TB I couldn't get this chunk to move by trying to pull it out. I had to take a screw driver and pry it off the inside of the intake to be able to reach in and pull it out.

So I take it my PCV valve needs replaced or cleaned?

It looked nasty but I got most of the chunks out this way. If I had the cash I would just pull the entire intake and clean it but I don't.

Anyone have recommendation for what I should do next?

Thanks

 

[Currency]

After cleaning my IAC valve my rough idle is gone. It now ides in park around 700 rpm compared to the 1,100 rpm before cleaning it. I can say I do recommend this for anyone with a rough idle as I had stated in my first post.

I will have to change my pcv valve sometime, about to call my local NAPA store and ask them about how much it costs with my 33% discount.

I do need to find something to clean my intake out with. Something like carb cleaner that will remove all of the old oil deposits.

Have to go update my registry and add some more things.

 

[Potomac30]

PCV valve is about $3.00, Motorcraft# EV-118. Check out the seafoam posts to clean your intake. That stuff costs about $8.00. I used the evap canister vacuum port under the throttle body to introduce the seafoam, other people use the brake booster line, I think that I will use the PCV port into the manifold next time, because that's where most of the sludge gets in. If you're having a lot of blow-by, check out the PCV catch can posts. I made mine out of some 1-1/2" ABS pipe and fittings - cost about $12.00.

Edit: maybe with big chunkies you shouldn't try seafoam, no telling what you'd break loose. Plus, after the seafoam, you should do an oil change and new plugs and it might start adding up too much.

 

[Currency]

PCV valve is about $3.00, Motorcraft# EV-118. Check out the seafoam posts to clean your intake. That stuff costs about $8.00. I used the evap canister vacuum port under the throttle body to introduce the seafoam, other people use the brake booster line, I think that I will use the PCV port into the manifold next time, because that's where most of the sludge gets in. If you're having a lot of blow-by, check out the PCV catch can posts. I made mine out of some 1-1/2" ABS pipe and fittings - cost about $12.00.

Edit: maybe with big chunkies you shouldn't try seafoam, no telling what you'd break loose. Plus, after the seafoam, you should do an oil change and new plugs and it might start adding up too much.

Thanks for the reply Potomac, I will try seafoam sometime soon. I've read about it being used here several time. I won't add it to my oil until spring time because I just changed my plugs not even 3,000 miles ago and don't want to spend the money to replace them so soon. I will be replacing my pcv valve later today.

Thanks everyone. My main problem has been solved

 

[JHolben]

Sorry to hear about your trouble. IMHO, if you have oil in that 3/4" black hose that comes from the oil filler neck, you should check your compression. It sounds to me like your oil rings and/or compression rings are failing and you are experiencing "blow by". Just a quick check. Disconnect the hose from the air breather and start the engine after it is hot and has been running for a while. If you see "smoke" coming out of the hose....you got blow by and the only thing that I know to fix that is to rebuild the engine.