Misfires and flashing CEL

[ecp]

Originally Posted by Stl-986

Curious why you think it's the injectors. From reading it looks like you have at least a wiring issue with the o2 sensor.

What sensor on the cylinder are you referring to?

do what JFP suggests. Very much doubt you have a bad cylinder as you would have more problems and noises if so.

To test the injectors the best thing to use is a NOID. It will tell you if an injector is getting power. You can also bench test each injector to see if they at least work, which I bet they all do.

i figured if it’s not spark, it’s probably fuel. this car is my baby and my daily so i am just distraught and frustrated. there is an ugly noise, if i could figure out how to share the youtube link. i bench tested and cleaned all injectors. they all work and all have a good spray. there was a good amount of junk that came out of them though. dark fluid. one of them smelled funky and had more deposits than the other, but still worked when i had it hooked up.

my aftermarket exhaust has the primary o2 sensor running off the cyl. 6 pipe before it merges. might be time to extend the wires and attach to the port after the merge for more accurate a/f instead of one cylinder.

[ecp]

Originally Posted by Stl-986

Curious why you think it's the injectors. From reading it looks like you have at least a wiring issue with the o2 sensor.

What sensor on the cylinder are you referring to?

do what JFP suggests. Very much doubt you have a bad cylinder as you would have more problems and noises if so.

To test the injectors the best thing to use is a NOID. It will tell you if an injector is getting power. You can also bench test each injector to see if they at least work, which I bet they all do.

coils and injectors are both getting power. i don’t know how two cylinders would both lose compression at the same time if that’s the case. and unfortunately it seems that way until i do a compression test.

[blue62]

Yes it sounds like a compression check is in order.
Let us know what you find.

[ecp]

Originally Posted by blue62

Yes it sounds like a compression check is in order.
Let us know what you find.

zero compression on cylinders one and two, 150 on three. didn’t bother with the rest.

i still can’t understand how they’d just blow at the same time like that. this is a 3 chain motor so i don’t know if that would make a difference or not

[ike84]

Loss of compression in two adjoining cylinders often points to a communication between the two, such as a cracked head, cracked cylinder, etc. I suppose it's possible that ****************ty fuel caused donation and wrecked something..

Sent from my POCOPHONE F1 using Tapatalk

[ecp]

Originally Posted by ike84

Loss of compression in two adjoining cylinders often points to a communication between the two, such as a cracked head, cracked cylinder, etc. I suppose it's possible that ****************ty fuel caused donation and wrecked something..

Sent from my POCOPHONE F1 using Tapatalk

I think I’m going to have to send it to porsche. if it does turn out to be fuel i’ll want to go the dealership route. it’s a real bummer, i was planning a road trip june 18th and was completely redoing the suspension before hand. Fingers crossed there is bad gas.... i can’t afford anything else

[blue62]

Just because I am curious.
You stated that your running headers.
Do you have other modifications to the car???

[ecp]

Originally Posted by blue62

Just because I am curious.
You stated that your running headers.
Do you have other modifications to the car???

just a 74mm TB and plenum, everything else is stock.

[blue62]

You could pull a fuel sample and send it out for analysis.
I don't have a clue where you would send it.

[ike84]

I agree with blues last post, that's really really dumb (and a rip off!) For Fuchs sake, that's $60 worth of parts. They're a pain to get at but drop the headers and you'll be done with both sides in under 2 hours.

I once worked on a truck that we couldn't quite figure out why it kept misfiring - replaced the plugs, cleaned the injectors, timed the distributor, still misfiring.

On a whim I suggested we drop the fuel tank - it was a total nightmare. Rust, mud, a rag (?!?)... Put a new tank in, truck ran perfect.

Anyway, bad gas (or not enough gas) causes problems. Lots of possibilities (I truly hope you haven't cracked your head or a cylinder wall) but I don't think that spark plugs are where to start. And ignoring a total loss of compression in adjacent cylinders is just dumb.

FWIW, I recently convinced myself I cracked the head and tried finding every article on the subject pertaining to these cars. It's virtually unheard of, even by the guys who rebuild these engines for a living. Cylinder scoring, yes. Trashed valves, yes But not head damage or blown gadgets.

Sent from my POCOPHONE F1 using Tapatalk

[Stl-986]

They could take a test sample all day long but that still wont tell them if there is water (generally speaking). they need to drain all of the tank and then the water will go to the top and fuel to the bottom.

You dont have to remove the headers for plugs, FSM doesn't even say to do that. Keep in mind he has it at the dealer so figure 4 hours labor and at least $30/plug. Little high, but I have seen dealers charging $185/hour lately.

[blue62]

Well my point was with O compression on two cylinders they want to change plugs.
WTF.
And charge $882.00 to drain the fuel and change plugs. Robbery.

[ecp]

Originally Posted by blue62

Well my point was with O compression on two cylinders they want to change plugs.
WTF.
And charge $882.00 to drain the fuel and change plugs. Robbery.

i’m 21, so they might just assume i’m a moron..... they said those plugs are fouled already and i said i know because i saw them when pulling them for a compression test. i had ran the car for maybe a minute while checking the wiring after installing them. He basically explained that they need to do their own diagnostic of the car, even though i did mine.

I daily drove a 72 karmann ghia for 3 years before i got this car. I know this is a totally different animal but i do know my way around a car.

[blue62]

Originally Posted by ecp

i’m 21, so they might just assume i’m a moron..... they said those plugs are fouled already and i said i know because i saw them when pulling them for a compression test. i had ran the car for maybe a minute while checking the wiring after installing them. He basically explained that they need to do their own diagnostic of the car, even though i did mine.

I daily drove a 72 karmann ghia for 3 years before i got this car. I know this is a totally different animal but i do know my way around a car.

Yes I think you do very well for a young fella.
I never take a car to a shop unless it is a recall situation.
So some of the thing shops do and the price they charge seems crazy to me.
I understand that they want to do there own diagnostics of the car.
But in the end it is still about the bottom line.
I also understand that they have to make a profit to stay in business.
But to me $822.00 to drain the tank and change plugs is nuts.

The real issue is your engine.
You say the plugs were fouled when you pulled them to do the compression check.
How were they fouled????
wet oil? black carbon? black carbon with sort of a powdery look ??
Grayish with sort of a powdery ash look???
Just trying to get a feel for what happened based on any info you have

[ecp]

Originally Posted by blue62

Yes I think you do very well for a young fella.
I never take a car to a shop unless it is a recall situation.
So some of the thing shops do and the price they charge seems crazy to me.
I understand that they want to do there own diagnostics of the car.
But in the end it is still about the bottom line.
I also understand that they have to make a profit to stay in business.
But to me $822.00 to drain the tank and change plugs is nuts.

The real issue is your engine.
You say the plugs were fouled when you pulled them to do the compression check.
How were they fouled????
wet oil? black carbon? black carbon with sort of a powdery look ??
Grayish with sort of a powdery ash look???
Just trying to get a feel for what happened based on any info you have

I’ve been burned by shops twice, and those were the last time i took my cars to anyone.

I installed a set of e3s out of curiosity in january and kind of forgot about it because the car ran well, and then re installed the lightly used berus that had maybe 2k miles on them last weekend. the e3s looked strange when i pulled them and i’ll post a photo if i can figure it out. i tried spraying sea foam into bank one from the intake boot (the one that connects the tb plenum to the runner with the hole for the valve) but never ran the engine enough to get it all through the system. I was trying to determine if it was a fuel issue by seeing if cylinders started firing when i sprayed it in (they didn’t)

But they looked wet, smelled a little oily, and a little like fuel and the tips were dark. looked a little like carbon to me but that could have been the sea foam loosening up deposits from the head and piston.

When i installed the berus they looked perfectly grey/tan and i’ll also attach photos if i can figure it out

[ecp]

Originally Posted by Stl-986

They could take a test sample all day long but that still wont tell them if there is water (generally speaking). they need to drain all of the tank and then the water will go to the top and fuel to the bottom.

You dont have to remove the headers for plugs, FSM doesn't even say to do that. Keep in mind he has it at the dealer so figure 4 hours labor and at least $30/plug. Little high, but I have seen dealers charging $185/hour lately.

That’s why i gave them the green light on draining the tank because i’m assuming they siphoned some out from the filler neck, and the tank is full.

I heard them say that for four hours of labor is $700, did the math and they’re charging $175/h

[Stl-986]

I dont disagree at all.

On the plus side if it is fuel related he wont be on the hook for the bill.

I doubt it's fuel though.

If it were me I would have them to do a leak down test, followed by scoping the cylinders and then providing video of each cylinder.

[blue62]

Originally Posted by Stl-986

I dont disagree at all.

On the plus side if it is fuel related he wont be on the hook for the bill.

I doubt it's fuel though.

If it were me I would have them to do a leak down test, followed by scoping the cylinders and then providing video of each cylinder.

Scoping yes. A leak down test???? If you don't have compression a leak down test is not going to tell you anything new. Spending money to find out something he already knows.
O compression on 2 cylinders.

[ecp]

Originally Posted by Stl-986

I dont disagree at all.

On the plus side if it is fuel related he wont be on the hook for the bill.

I doubt it's fuel though.

If it were me I would have them to do a leak down test, followed by scoping the cylinders and then providing video of each cylinder.

That’s why i’m really hoping it is fuel. i mean i made it maybe 600 feet away from the station before it called it quits. the pump was a little slower than usual, and didn’t smell as strong as usual..... but then again the m96 has a reputation, and i also have a reputation of having strange coincidences

[Stl-986]

I'm thinking the scope is going to help you figure out the problem. I haven't seen these happen with these cars, but anything is possible.

With my jetski's if the wrong plug is used or it is running too rich the piston's are known for getting holes burned out on the top of the piston, which in turn obviously causes no compression. On 2 cycle ski's this is always cause of not running the right mixture. Doesn't apply 100% to a car obviously but I think it COULD be possible to happen depending on the gas quality. Scope will be pretty obvious.

There are some very cheap cameras you can get on amazon that hook up to your phone, just for the future. Think I got one for around $15. Quality isn't great, but it does it's job.