CEL back on, cylinder #1 misfire

[RumpRanger98]

So a few days ago my CEL came on . I took it to my cousin (owns his own car shop) and cylinder #1 misfire code came up. Plugs are new, inspected looked new still, plug wires are new, IAC is new. He smoked tested it for intake leaks, none found. compression tested, cylinders 2,4,5,6 tested around 150-160, and cylinders 1,3 at 120.... Is that low enough compression to cause a misfire?

He ran some fuel injector cleaner through it and cleared the codes, and I drove it around the last couple days, and the fuel injector cleaner made throttle response noticeably better. I was hoping problem solved. Sure enough, on way home from work, I started car up, and after 5-10seconds of running the CEL popped on again. Idiotzone said same code had popped up, misfire cylinder 1.

The truck seems to run great, engine is a little rough on reving in lower rpm ranges. But seems ok in gear and driving. I won't be seeing my cousing until Monday. Last I talked to him he was reccomending to take the valve cover off and check a few things out. I can't remember and I might be saying the wrong things, but he had said something about the valves( i think) could be burned or flattened, or something bent. Im not sure, I think he is thinking something internally in the motor is causing this problem...

If anyone can help me figure this problem out itd be much appreciated. I don't like throwing money at problems. What can I check and test that could be causing this problem?

 

[betomonroy]

Check for a dirty Throttle body and clean it very good with it removed from the engine.
You may also be experiencing a bad coil pack or a bad CMP or CKP.
I don't think You have a bad head but you do have two cylinders with what I consider low compression (though they are not next to each other).
Low RPM combined with rough idle can be caused by a clugged up throttle body but this will not cause such code. Clean it up anyway so you'll get a better city mileage and a smoother idle.
BTW... the only way to have bent valves would be by breaking your timing gears or chain causing the valves to come in contact with the pistons... and i seriously doubt this is the case... I think your relative is trying to turn You into his Piggy Bank. Be careful.

 

[bobbywalter]

probably a bad valve spring or something.

is it losing coolant? if all checked out at theshop maybe its seeping coolant...cracked plug/wire/pack ect.

 

[RumpRanger98]

my cousin has never done me wrong, or even a stranger wrong. My good friend back when he was 16 took his first car to my cousin, not knowing who he was or anything. Andmy cousin told him to fix something on his car and sell it because it would be nothing but problems, when he could of sat there and fixed stuff and milked him for money. I doubt he would do that to me.
anyways.....
I think its a bad coil pack too.

I noticed driving home from my buddies house a few minutes ago. when the engine is at 2600-3300 rpms, no matter what speed. i can hear sparking, just like when my cousing tested for spark by lifting the boots on the plug wires. Is my coil pack starting to go bad? seems to run normal other than the cel.

I took the intake tube off and TB is CLEAN. I doubt a dirty TB would throw a cylinder #1 misfire 2x in a row.

Leaking coolant? I just flushed the sytem. oil is perfect, not milky at all. and no drips anywhere. looks like somewhat new waterpump, maybe 1 year old.

its not a cracked plug(is that possible?) plugs are new, wires are new, so they aren't cracked. But I think its the coil pack. Seems almost the miss is intermitent.

The CEL pops on ASAP the first miss happens right? I reset the codes and it takes at least 20-50 miles before the same code pops up.

im leaning towards bad coil pack, my cousin seems to lean towards bad valve spring or something internal. he thinks pack is good only because it was sparking when he tested it. But from what ive read, people have tested there pack and its sparks on all 6 but, was still bad....

 

[RumpRanger98]

Ok so I read it 2 hours ago, but cant find it know. Someone else on here had posted in the past they had an engine rattling sound from 2.9k-3.2k rpm. real close to that area. Im having that same thing. Im trying to find the thread on it but cant find it through searching. I think they had replaced the coil and all worked well.

someone has to know what im talking about, im so angry i cant find that thread right now. Guy describe a rattling type sound only around the same rpm,s im getting the same type of sound. im pretty sure the sound is sparks. I want to read his thread to figure out what he replaed, i think it was the coil pack. damnit, should of bookmarked.

 

[bobbywalter]

well, when its dark get a spray bottle of water and start spraying and revving the engine and watch for sparks.


no sparks or any increased missing would lead me to the coolant leak/or valve train issue.


cracking a plug on install is common. they may not be readily visible but will be happy to leak current.

a coolant seep/burnt seat can be minor enough to just sap some current or throw off compression and never effect the oil


these ...most problems are impossible to effectivly diagnose on line..

 

[RumpRanger98]

well, when its dark get a spray bottle of water and start spraying and revving the engine and watch for sparks.


no sparks or any increased missing would lead me to the coolant leak/or valve train issue.


cracking a plug on install is common. they may not be readily visible but will be happy to leak current.

a coolant seep/burnt seat can be minor enough to just sap some current or throw off compression and never effect the oil


these ...most problems are impossible to effectivly diagnose on line..

So i had the codes erased last night. This morning I jumped in to go to work at 3am. And I decided to open the hood and check for sparks. I didn't want to rev it up because my girlfriend was sleeping inside, guess the neighbors would get upset too.

Anyways, engine running, hood open. CEL is OFF(had it erased last night). I didn't rev and mist water, I just let it idle and misted water around coil pack and the #1 plug area. I couldnt see any sparks or notice any change in motor running. So I jumped in to go to work and the CEL was on, last time it took about 40 miles before the cel came on, this time. maybe 2 miles. Did the water get into the coil pack and trigger the CEL maybe? Im getting tired of going to the auto zone and using there scanner, and i think there tired of seeing me so I dont know what this code is. assuming since the last 2 were misfire cylinder #1 im guessing its the same.

I got the rest of today off and tomorrow off, but its raining like crazy, But if anyone can give me some tips on what to look for or check or some tests i can do. something, anything, to help me eliminate some possibilities and find the problem.

Im going to try to swap a different plug into that cylinder, to try and eliminate that from being the problem

 

[RumpRanger98]

Check for a dirty Throttle body and clean it very good with it removed from the engine.
You may also be experiencing a bad coil pack or a bad CMP or CKP.
I don't think You have a bad head but you do have two cylinders with what I consider low compression (though they are not next to each other).
Low RPM combined with rough idle can be caused by a clugged up throttle body but this will not cause such code. Clean it up anyway so you'll get a better city mileage and a smoother idle.
BTW... the only way to have bent valves would be by breaking your timing gears or chain causing the valves to come in contact with the pistons... and i seriously doubt this is the case... I think your relative is trying to turn You into his Piggy Bank. Be careful.

TB is clean. There are times where it revs up fine in low rpm's. which im assuming all are firing at that point. But sometimes its rough in low rpms, which is when its missing.

I think my cousin was thinking valve spring, not valve itself. Like i said, i didn't recall exactly what he was saying it could be, i just remember it recquired taking valve cover off.

 

[RumpRanger98]

does anyone know what that noise could be im hearing around 2600rpm-3300rpm? It sounds like a small metal rattle. Sounds more like when you pull boot off the coil pack and sparks arc fast. Doesn't seem to do it if I get above that rpm level and then just coast in gear. But when im giving it any gas even the slightest at that rpm range, is when i hear that rapid sparking, or metal rattle.

 

[RumpRanger98]

Ok so to hunt down my misfire problem I pulled out my multi meter and started testing some things to rule out some possiblities.

I pulled the cylinder 1 plug and inspected closely. no visible cracks. looks normal. I put in autolite platinums, I hear you can use these instead of motorcraft . I can't remember what brand wires I put on, could this have any effect? seems only 1 cylinder is misfiring.

I checked coil pack, all 3 ohmed at 0.8k I believe range is 0.3k-1.0k
Is it possible for the coil pack to fail intermitently and cause a voltage leak on the cylinder 1? would like to rule this out if possible.

I checked ECT, working fine, in proper spec

I checked IAT (im sure it doesnt effect my problem) in proper spec

IAC was 10.0 ohms, in spec is 7.0- 13.0

TPS was 0.66k ohms at WOT and seemed smooth to variate from closed to wot. closed it reads 3.68k ohms I think this is normal, can someone confirm please?
stupid chilton book doesnt specify what it should be at, just that it should fluctuate smoothly.


I unhooked battery to do all this so code got cleared. I went and drove about 10 miles to get ecu reprogrammed or whatever. CEL hasn't come on yet, but it will soon.

I dont know what else to check. I think im going to have my cousin pull the valve cover and check the valve springs. those can cause low compression and thus a misfire correct?

 

[bobbywalter]

well i too think it is a spring or some valve train issue with a seep or maybe it is just a seep of some coolant.

doing a hot leakdown may help but small leaks can still be hard to find.

t dont have to dead miss to set the code. what does a balance test indicate? i dont remeber what is needed for those.

investing into a good obd 2 tool is money well spent if you work on your own stuff.

 

[RumpRanger98]

When he went in and replaced my valve cover seals 2 weeks ago he did tell me it looked like new(used im sure) heads were put on. perhaps the one could be cracked. I am getting 120 on cylinder 1 and 3. cylinders 2,4,5,6 are all 150.

what is a balance test?

whats a hot leakdown test? pressure the cooling system to see if it loses pressure thus water seeping through headgasket or cracked head?

Ive been reading threads of problems people have had, and 1 guy, 3.0 motor, had cylinder 1 was 65 and 2 was 120. He pulled the head and the head was cracked on cylinder 2. not sure what was up with cylinder 1. but i would of though cylinder 1 being lower would of had the crack.

It doesn't seem like im losing any coolant. im going to watch the resevoir very closely now.

If the head is cracked, how much does one cost and should i just get one from a jy or buy new/reman?

Thanks for the help bobby

 

[RumpRanger98]

well i too think it is a spring or some valve train issue with a seep or maybe it is just a seep of some coolant.

would a bad spring cause that noise i described above at those rpms and not others?

I wish I had the money to buy a scanner, whats a good one cost anyways and what one is reccomended?...edit I just found one on ebay I liked and seller had lots of great feedback on it. should be here in 4 days maybe 5 because of sunday. but this will be very nice to have.

 

[bobbywalter]

would a bad spring cause that noise i described above at those rpms and not others?

I wish I had the money to buy a scanner, whats a good one cost anyways and what one is reccomended?...edit I just found one on ebay I liked and seller had lots of great feedback on it. should be here in 4 days maybe 5 because of sunday. but this will be very nice to have.

it could, and reasons like this is why i quit trying to help people online. i just dont communicate well. its possible the valve stem had a bur or somethin and wiped the seal a lil ect ect..i have messed them up a few times and had to kick myself in the ass....without going thru it personally its too hard to say.


inner chamber cracks ect wont always show up on a cooling psi test. unless the engine is already at op temp ect. the low compression alone could be the trigger, and switching to a different plug would eliminate it.


its alot to take in.

 

[RumpRanger98]

the low compression alone could be the trigger, and switching to a different plug would eliminate it.

im not sure what plugs were in there when I bought it, but I drove it for about 150 miles with no cel, I changed plugs and wires, and maybe 40 miles tops, it started the cel issue with misfire cylinder 1. The wires I put on were same as ones I pulled off, but new. I forget the brand.

Im assuming switching to a different plug would be going and getting some motorcraft ones? which ones are reccomended and would give me best spark for a low compression cylinder?
im off tomorrow so Im going to go try to find a place around here that sells motorcraft plugs. probably change the fuel filter too since i dont know when that was done. probably pcv valve as well. should these all be motorcraft parts or is oem ok?