Engine miss??? Big time frustrated...

[Mike93]

Engine miss??? Updated...now calling those who have done the atx/mtx swap

Ok...where to start. I've been dealing with a problem that has been going on for about the last 10,000 miles and have tried many fixes and stumped everyone along the way, here's your chance to shine I've pulled codes and found nothing.

Anyway, I'm pretty sure that I have a miss somewhere, feels like I'm running on 5 cylinders. I notice it most at idle where I get a pretty significant vibration that causes the dash to shake and the driver side headlight to wiggle (must be annoying to other drivers at night) It will come and go, but not disappear, and is more of a fluctuation of vibration. While driving, it feels like I'm running at about 75% of the engines power. Cruising the higway it feels a bit smoother but still slightly noticable. WOT it will stumble and jump it's way up the rpm band, still pulls okay but not all there.

What I've tired:
*New plugs (Autolite 3924's) 3 sets now, gapped to .044
*New wires (AC Delcos) and 20k Motorcrafts
*DIS, coil, mass air from a parts car (known to be good)
*New fuel filter
*I've tested plugs, wires, and fuel injectors individually and all work fine. Plugs and wires were removed for testing...removed intake and plugged up a home made fuel injector testor that allows me to see the spray pattern. Injectors passed.


Wierd things:
1) Had a bad EGR valve, pumping a lot of crap into the intake...figured that was causing a problem. Blocked it of...nothing changed.
2) Pulled timing chain covers...two cam sprockets lined up fine, crank sprocket off a few teeth...figured this would be a problem...adjusted it...nothing changed. Unless I'm 180 degrees off on the crank???
3) Put a timing light on #1 coil wire and it would show spark to be 'on' for 5 or so hits and 'off' for 2...so it was missing, but not consistently. Put it on another wire (forget which one) but it sparked perfectly. So something wierd going on here...
4) Had a stock y pipe that came from the mtx parts car, I suspected clogged cats but can't determine if this was true. Anyway, I replaced this with a friends Sho Shop catted pipe and the car drove great, felt VERY strong and I didn't notice vibrations. Then, gave the pipe back and replaced it with a Summit pipe and vibrations are back. This seems strange that the car responded so differntly to differnent pipes...

I don't where to look next...thoughts???

 

[djcannon]

Check for oil in your plug wells. Remove the front, middle spark plug wire and shine a flashlight down there. Try to look for the oil with the plug still in there. If there's oil there and you take the plug out, you'll get oil in your cylinder, so you'll want to suck it out first before removing the plug.

It could be so many other things, but check your plug wells for oil first. Common problem. If you're valve cover gaskets have never been replaced, I'd bet that's it.

 

[Mike93]

Check for oil in your plug wells. Remove the front, middle spark plug wire and shine a flashlight down there. Try to look for the oil with the plug still in there. If there's oil there and you take the plug out, you'll get oil in your cylinder, so you'll want to suck it out first before removing the plug.

It could be so many other things, but check your plug wells for oil first. Common problem. If you're valve cover gaskets have never been replaced, I'd bet that's it.

Forgot to mention this in the original post...there has never been any oil in the plugs wells, this motor has been very well kept by the previous owner and received all maintenance at a Ford dealer at proper intervals. I'm the third owner...second owner had it from 15,000-175,000 miles...it now has 196,000. I have never seen a car in as good of condition as this one is/was!

Also, I've probably had the plugs in/out at least 15 occasions in the past few months...fwiw

 

[Ishodu]

Have you checked your spout connectors? There is a how to in the "how do I section"

 

[Mike93]

Have you checked your spout connectors? There is a how to in the "how do I section"

You mean have I checked to see if they're not completely plugged in??? Only time I've dealt with the spout was when checking timing...and I'm pretty sure it's all good.

 

[thecrew2999]

well the timing belt if its off then its time to change it reguardless and check the tentioner and all make sure its good. also as i learned the belt olny goes on one way so keep that it mind. long as all the lines are lined up its in, no question.
check the crank position sensor and cam postition sensor.
make sure there is no vacuum leaks at all. check all wiring if any is bad grounds etc fix it.
i dont think your missing personally i think its a weak ground of vacuum leak.
and if it is i know this hasent happened to anyone really but change your coil pack its a good possibility. i know there is a little cylnder thingy attached to it that if thats bad it acts all weird. i learned that when i was doing my swap and someone had steped on it....

good luck just check and recheck and check some more you'll find it... spend a night with your car just you the car and a case of beer. get to know your car... love your car.... just dont get all sick on me lol

 

[Mike93]

well the timing belt if its off then its time to change it reguardless and check the tentioner and all make sure its good. also as i learned the belt olny goes on one way so keep that it mind. long as all the lines are lined up its in, no question.
check the crank position sensor and cam postition sensor.
make sure there is no vacuum leaks at all. check all wiring if any is bad grounds etc fix it.
i dont think your missing personally i think its a weak ground of vacuum leak.
and if it is i know this hasent happened to anyone really but change your coil pack its a good possibility. i know there is a little cylnder thingy attached to it that if thats bad it acts all weird. i learned that when i was doing my swap and someone had steped on it....

good luck just check and recheck and check some more you'll find it... spend a night with your car just you the car and a case of beer. get to know your car... love your car.... just dont get all sick on me lol

How do I go about checking the crank and cam sensors? I've checked time and time again for vacuum leaks and have come up empty. As far as grounds go...how many are there? I remember the one on the intake near the firewall on the passenger side, any more anywhere???

Despite the thread title stating I think I have a miss...I do agree with you that it could be something stupid like a vac leak, bad ground, etc,....except I haven't found it yet:cry: I do have (another) spare coil I will try tonight after work.

I think I sense your sarcasm about checking and rechecking to get to know the car, etc....if I had a dollar for every minute I've spent messing with this thing I'd have a lot of money!!!

I don't know if it's coincidence or not...but these issues appeared right around the time of the mtx swap. I had a few other issues to work around at that time that may have hidden this missing issue. Two things that stand out were a faulty pressure plate that basically made it impossible to drive....there was such a fine line for clutch/gas use that too much/too little resulted in HORRIBLE engine shaking....enough to break a motor mount, disconnet the y-to-cat back bolts, and basically leave me with soiled shorts everytime it happened. So, that and then having a busted motor mount caused some vibrations...I dunno if this has anything to do with it but I threw it out there.

How has your swap been going? Did you do like I did and kept all the 3.2 accesories/belts/computer??? Any issues with yours????

Thanks for the replies so far.

 

[thecrew2999]

my swap went beautiful... i made my own dumb mistake tho without thinking.
i think i got so into swapping stuff that i forgot something important. when swapping heads you need new head gaskets lol, that had me mad.
all went well and car runs beautiful.
i had a vaccum leak tho which game me some problems at first. my intake wasent down enough and sucking some air which gave it a real funny idle.
i learned a lot threw the swap and im glad i did it, now i feel like i know my car better then i know my g/f lol
when i did the swap i kept the atx computer even tho i was oringionally gonna swap everything comp and wiring included but i kept it more simple since stripping the donor car took me about 5 days straight on its own.
i wanted it done so i could play.
anyways the sarcasim is olny joking i do understand the fustration and i know how it can get to ya but just dont give up and when ya think ya checked everything sometimes you missed something.
im suprised tho you couldnt pin point this better... did you do the swap alone or with help?
i did my swap by myself and honestly i think i can find everything on my car blindfolded.
beforfe i say anything else just check the coil pack.
hope it works for ya man..

 

[thecrew2999]

o your the guy who moved the a/c drier and used atx / mtx mounts..
sry i just checjed your car domain.
car looks good by the way .
in my atx to mtx swap i kept all that stuff where it was and used extreme reinforced motor mounts and didnt motify them at all.
the a/c and all dosent cause any problems even tho i had to take time to reroute stuff.
3.0 accessories tho. had to do some wiring splicing here and there like alt but everything works flawless.
anyways let me know how the coil pack swap goes.

 

[Mike93]

o your the guy who moved the a/c drier and used atx / mtx mounts..
sry i just checjed your car domain.
car looks good by the way .
in my atx to mtx swap i kept all that stuff where it was and used extreme reinforced motor mounts and didnt motify them at all.
the a/c and all dosent cause any problems even tho i had to take time to reroute stuff.
3.0 accessories tho. had to do some wiring splicing here and there like alt but everything works flawless.
anyways let me know how the coil pack swap goes.

Yep, that was/is me...glad to hear you got yours working well. I swapped yet another coil pack on tonight and got the same results; nothing changed. As I was poking around in there I was listening for anything abnormal. While quickly opening the throttle body blade I could be a whoosh of air blowing out of the airbox...something not noticable in the car. Also, I pulled the connector off the coil to **** the car and when doing so there was a healthy gasp of air leaving the airbox...what's going on here???

 

[dpsutphin]

Does the engine miss while the car is sitting still? If not, you may have a bare spot on an injector wire or some other wire that is touching something metal when the engine moves under acceleration which could cause the intermittent problem.

Just follow the wires and tape up any bare spot with good quality electrical tape. Pay special attention to the area where the wires cross the intake.

Good luck.

 

[Mike93]

Does the engine miss while the car is sitting still? If not, you may have a bare spot on an injector wire or some other wire that is touching something metal when the engine moves under acceleration which could cause the intermittent problem.

Just follow the wires and tape up any bare spot with good quality electrical tape. Pay special attention to the area where the wires cross the intake.

Good luck.

Yes the engine has it's miss, or whatever it's doing, while the car is still. I will check again to see if any of the wiring anywhere is 'not right'. However, when I had the engine out to so the swap I had cleaned and taped up the wire harness, but I'll keep looking.

 

[esahlin]

My guess.....is possibly head gaskets or some of the valves/valve seats are leaking. Get a compression tester and test the compression in each cylinder...you should do a leakdown test also if possible. 196,000 miles is an awful lot for any engine especially a high reving motor. Probably one or a few of the valve seats are just worn out and leaking a bit. A head gasket leak would give you a miss and a loss in power also. Do the compression and leak down check...that will tell you more.

 

[Mike93]

My guess.....is possibly head gaskets or some of the valves/valve seats are leaking. Get a compression tester and test the compression in each cylinder...you should do a leakdown test also if possible. 196,000 miles is an awful lot for any engine especially a high reving motor. Probably one or a few of the valve seats are just worn out and leaking a bit. A head gasket leak would give you a miss and a loss in power also. Do the compression and leak down check...that will tell you more.

Oops...forgot to mention this as well I had done a compression test a few thousand miles ago and all cylinders came up in the 180-200 range. Have not done a leak down though...

I'm still wondering about the whoosh of air coming out of the airbox when I apply throttle...

thanks again for all the reponses

 

[esahlin]

Although I wasnt there to experience the whoosh of air out of the airbox, all I can think of is an intake valve open a little or alot on the compression stroke (worn valves/seats or the timing belt is off on alignment a little). Just brainstorming here......you could have leaky valve stem seals that are letting in a bit of oil into the cylinder causing a miss or if its a bit of an amount of oil leaking past then you'll notice a power loss.....does you car lose oil between oil changes....can you tell if it emits blue smoke out the exhaust on startup?

Your timing belt could have skipped a tooth or two (it stretched or?).....I would check it to make sure its on/aligned perfect. Maybe repeat the compression test if you decide to do a leakdown here in the future. Good luck....kinda frustrating and tiresome work I bet.

 

[Mike93]

Although I wasnt there to experience the whoosh of air out of the airbox, all I can think of is an intake valve open a little or alot on the compression stroke (worn valves/seats or the timing belt is off on alignment a little). Just brainstorming here......you could have leaky valve stem seals that are letting in a bit of oil into the cylinder causing a miss or if its a bit of an amount of oil leaking past then you'll notice a power loss.....does you car lose oil between oil changes....can you tell if it emits blue smoke out the exhaust on startup?

Your timing belt could have skipped a tooth or two (it stretched or?).....I would check it to make sure its on/aligned perfect. Maybe repeat the compression test if you decide to do a leakdown here in the future. Good luck....kinda frustrating and tiresome work I bet.

I do lose a little oil between changes, but I think that may be attributed to a leaky main seal on both ends. I am trying to track down a leak down tester as that should answer some questions...and I'll do another compression test. No smoke on startup. I also checked for vacuum leaks but came up with nothing. I used a can of carb cleaner and sprayed away...I'm thinking of going to a shop and having them run the smoke machine to be sure though as a can of carb cleaner can only reach so far.

A few questions, some may be repeats but I didn't get an answerl:

*air coming out of the airbox when applying throttle, why?
*anyone run Autolite 3924's and AC Delco wires and found them to not work well? I'm probably going to pick up some Motorcraft plugs...
*would a faulty o2 sensors cause anything??? I thought a light would be thrown if it were...
*Even though injectors, plugs, and wires worked when tested individually outside of the car...could it be possible that in the car something is not allowing one of these to function???

 

[NiNeTy Fo SHO]

Just with a quick glance over the thread...I would look for some motorcraft wires. It sounds like the problem I had when my stock wires started going out. I would get a miss...then a plug wire would fall off. Put it back on...everything is ok...then another miss.

No codes would tell me that its wires or spark plugs. If you have motorcraft plugs...I would look at the wires. In my opinion...the SHO is very picky...the AC delco's may work on some...or with certain plugs...etc. But you know motorcraft plugs with motorcraft wires works damn good.

 

[CerberuS]

I do lose a little oil between changes, but I think that may be attributed to a leaky main seal on both ends. I am trying to track down a leak down tester as that should answer some questions...and I'll do another compression test. No smoke on startup. I also checked for vacuum leaks but came up with nothing. I used a can of carb cleaner and sprayed away...I'm thinking of going to a shop and having them run the smoke machine to be sure though as a can of carb cleaner can only reach so far.

A few questions, some may be repeats but I didn't get an answerl:

*air coming out of the airbox when applying throttle, why?
*anyone run Autolite 3924's and AC Delco wires and found them to not work well? I'm probably going to pick up some Motorcraft plugs...
*would a faulty o2 sensors cause anything??? I thought a light would be thrown if it were...
*Even though injectors, plugs, and wires worked when tested individually outside of the car...could it be possible that in the car something is not allowing one of these to function???

3rd * = Faulty o2 always gives a code out. And it usually comes to bad fuel economy when not working properly.

 

[Mike93]

3rd * = Faulty o2 always gives a code out. And it usually comes to bad fuel economy when not working properly.

Thanks, no codes thrown and I've been getting 325ish to a tank.

Anyone have thoughts on the other questions???

*air coming out of the airbox when applying throttle, why?
*anyone run Autolite 3924's and AC Delco wires and found them to not work well? I'm probably going to pick up some Motorcraft plugs...
*Even though injectors, plugs, and wires worked when tested individually outside of the car...could it be possible that in the car something is not allowing one of these to function???

 

[CerberuS]

* Very weird , its like compression of the pistons is leaking through intake valves????Getting back in the intake...unlikely. Deal the other issues first , most likely its gonna resolve this one.

*Its a hit or miss on what ive read , basicly NO ONE ever stated they had issues with the motorcraft plugs , best bet. As for the wires , i think the delco was doing their job , never seen anyone saying they were crap....

*Even a fully test wire or plug or whatever sensor (outside vehicule) can be faulty. Its very tricky ,sometimes they seems ok , but when in heat-pressure-cold-whatever , they fail , and when in normal condition , there ok.
Best bet is to try a new set and see by elimination , and return the package if its not that (local part store).