SOHC Still hesitates!!

[CHuntMD]

So far:
Cleaned MAF with electronic parts cleaner
Replaced IAC
Replaced TPS
Replaced plug wires (but not plugs)
Cleaned TB buterfly
BG 44K fuel injector cleaner

X is 97 w/99,000 miles

Problem: Randomly, the X will hesitate when giving gas usually mid throttle. The more you press the more the engine misses. Happens on wife's 22 mile comute but is unpredictible.

I'm leaning towards coil pack but wondering what else to look for/at/test before I spend bucks on a coil pack.

Thanks
Chris

 

[Strike12]

Id check to make sure you dont have any cross firing first . You can do this in a dark place or at night , just look in the engine compartment and see if you see any kind of sparking . Look all along the plug wires and around the coil tower where the plugs attach .If you see any sparking around the towers it could be a cracked coil pack . If its the wire then just change them . You can test the secondary resistace of the coil by checking the resistance between each of these secondary towers >1-5 , 4-3 , 2-6 (4.0L) 1-6 ,3-5 ,4-7 , 2-8 (v8) resistance should be 6.5k ohms - 11.5k ohms and within 10% to each other. This is the simpliest test I can give you > I have another method but requires a engine analyzer that actually checks high voltage output , but those test as I stated should give you good results.

 

[CHuntMD]

I'll look at it Wednesday night and see what I call see in the dark

Any idea what a coil pack costs?


Chris

 

[TPLYNCH]

Could be your FPR starting to crap out too. If it dumps too much gas, it could cause your problem.

 

[daniel cauchon]

ok I had the exact same prob, last week end on a trip ...It was doing the same thing when accelrating and going up hill...found the prob with one of my plugs defective...I change all the plugs and the wires ans it runs great...gave it a try slam the pedal to the floor on the highway and realy no more prob... I would definitly check the plugs..how long are they there ?

 

[CHuntMD]

Is FPR = Fuel Presure Regulator???? Any idea where is it or what it looks like???


Plugs, will need to look at records to see when they were replaced but I know it has not been done in the last year. It might be prudent just to spend the $30or so on new motorcraft plugs (that is a car of worms on this board

I did get a quote from fordpartsnetwork.com

DGE446 Genuine Ford coil $ 99.99
AGSF22PP Genuine Ford spark plug $ 4.99 ea.

 

[daniel cauchon]

Model ? year ? milleage ?

 

[Strike12]

I got some prices between 59.00 and 91.00 , depends on which brand you want . Try this link they got good prices and no shipping over 50.00. http://www.autopartsgiant.com/referal/

 

[CHuntMD]

daniel... Are you asking about my X? If so it is a 97 SOHC XLT almost at 100,000 miles and paid for!!!

My 92 X had a lot more "issues" before it reached 100k miles, the tranny was the worst IMHO.

My 94 4.0 OHV 5sp Ranger SC is still pulling strong at 118k miles. original clutch to boot.

Chris

 

[daniel cauchon]

Yes Chund I was asking just to see if you plugs were over due...but anyway I were I would definitly change them...keep us posted..

 

[CHuntMD]

I did the dark garage turn on the engine and look for light. Didn't see anything even when goosing it. Yes I did plug the under-hood light and wait for the garage door light to go out)

It is COLD here in Wash DC area so I'll do the ohm test this weekend and change the plugs (what joy that is)

I wish it was more consistant.

Chris

 

[TPLYNCH]

Here's a link to the How to Replace the FPR from the Singleton Maintenance site. Dead Link Removed

 

[Strike12]

I would also change the plugs if they havent been done in a while . Youd be amazed by how many problems have been solved by doing a plug change , plus its not to hard to do and inexepensive. Did you do a code test on it? Well good luck and keep us posted , fixed or not.

 

[CHuntMD]

Well It took awhile but I managed to change the spark plugs on Saturday. The passenger side is a rear chore.

Pics at

http://www.peake.com/occ/My97Explorer/

Any idea what the globe thingy is?

I though the plugs had fixed the hesistation but it happened to me last night while driving from annapolis to home (about 35 miles). After highway speed then slow down for a light and then start to accelerate right around the 30-40mph. The more gas the worse the engine shakes. Letting off the gas and then reapplying pressure fixes the problem. I was also told that earlier that day after highway speed then sitting at a light the idle is a little low and rough and the first press of the gas pedal it "seems" stuck.

So far, replaced the IAC, TPS, plugs and wires, cleaned MAF. I'm picking up a digital multitester today so I can test the coil when it is hot.

Chris

 

[Howard]

That globe thingy is a vacuum reserve/valve for all the heater vent controls. Mine had somehow been hooked up the wrong way round and the vent controls didn't work.

The hesitation could be lack of fuel pressure or a sticking injector. Run some cleaner through.

 

[CHuntMD]

Thanks for the info on the globe thingy.

I run BGG44K every 7,500 miles as recommended. I'm going to test the coil pack resistance cold vs. hot once I get a better multimeter.

It was mentioned the Fuel Pressure Regulator could be the problem since I think it is located near the throttle body so maybe it has become heat sensitive.

The problem is not consistent that is for sure.

Chris:

 

[CHuntMD]

Well, I thought the X was fixed but I got another check engine light on the way home. During the "Big Snow Storm" here in east the X got a CEL P1151/P1152 so I took it this AM to Pat Goss's shop (the same guy on PBS/Speedvision Motorweek)

They diagnosed leaking intake manifold gaskets so both the upper and lower were replaced.

The day before (but after the weekend CEL) I replaced the coil pack but I think the orginal was ok atleast the secondaries all tested ok. Actually the new and old coils tested within .3 to .5 of each other while cold.

So I'll be heading back to see what the current CEL is. Luckily the spouse still remembers how to drive a manual tranny I must admit the SOHC 4.0 really can scoot compared to my Ranger's OHV 4.0

Chris

 

[rokke17]

TPLYNCH
I have to tell you, your sig is great.

 

[TPLYNCH]

Thanks!

 

[CHuntMD]

Hopefully this problem has been put to bed. Last night's CEL turned out to be a bad O2 sensor.

Anyone know what a decent price is to replace the upper and lower intake gaskets (O rings???) Look like the same ones that come in the cam tensioner kit??

Chris