Removed fuel injectors, and oops.

[compleckz]

i've been trying to track down my misfiring problem, my current step was checking the fuel injectors, i was going to check out the #4, and either clean it or swap it with another, to see if the problem moved with the injector..

well all went well till the injectors came out, they came out pretty easy but something was missing.

the o-ring was still in the hole, and i was able to carefully fish it out, but the plastic end piece is MIA. i've never dug deep into this engine before, i don't know anything about it, so has this plastic piece fallen all the way into the cylinder?

also what is this thing, and why is it so ass-dirty?

the o-ring gasket for that thing was broken:

and it goes into the upper intake here:

it seems like with having to put a new gasket under the fuel rail, and all the stuff that needs to come off (and possibly more now) it might make sense to do a bit of an overhaul on the top end.. i have an oil leak from somewhere, maybe valve covers, and im getting this misfiring problem, which could be a valve..

what does everyone think about.. everything?

 

[MAKG]

That plastic "hat" shapes the injector spray pattern. You MAY be able to find it in an injector O-ring kit. If you're lucky. If it's not sitting in the lower intake right now (unlikely), there is no other place it could have gone aside from through the cylinder.

The absolute first thing I'd suggest under your circumstances is a cylinder leakdown test. If you have a leaky valve, you need hundreds of dollars of machine work (valve job), and this may affect your strategy. It's possible that the injector hat caused a warped or burnt valve.

I think you're looking at a fouled EGR valve, but I'm not having the easiest time making it out. EGR goes from exhaust to intake manifold. If it goes from valve cover to intake manifold, it's part of the PCV system. Either can be a source of vacuum leaks, and either can get plugged with oil sludge.

I fix valve cover leaks for no other reason than the smell drives me batty.

While you have the injectors out, I'd change every one of those O-rings. They cost less than $1 apiece. Lubricate them with Vaseline or you'll cut them on installation and make a nasty fuel leak. BTDT.

 

[Mutant Pony]

You should have run a compression test before tearing the motor apart. The oil leak could be the intake end seal at the back of the motor, which would require removal of the lower plenum. Upon removal of the lower plenum you may find the end of the injector. Probably not though, It is probably gone forever. I wonder if it is stuck in the intake valve of that cylinder?

 

[compleckz]

so should i change the injector, put it back together and then do a compression test? i don't have a compression tester, else i would have done it, i was just planning on taking it apart and checking the injector/replacing...

im not sure if the hat came off during removal, or if thats what caused the problem initially. so its unlikely its anywhere but in the cylinder, and i cant get it out most likely without pulling the head.. i wonder if i can find a small claw grabby thing to get it out..

so yea i really don't know what to do.. i guess first i need to figure out if that plastic hat is in the cylinder.. if so try and get it out... if its not, then change the injector.. reassemble, see how it runs.. if badly, compression test.. (i already checked plugs, wires, coil)

btw, money isn't a big deal, if it needs work, it needs work, and i need to pay up.

also i have a car for a daily, so downtime is just annoying, but not a huge problem.

 

[MAKG]

No, do a leakdown test exactly as the engine is now. All you need is for the heads to be installed. Just pressurize each cylinder to 100 PSI at TDC/compression (or just TDC if the rocker shafts are off) and listen for hissing in the exhaust pipe and lower intake ports.

 

[compleckz]

well, i found it! was in the intake manifold, just BARELY hanging on... that EGR tube apparently is only supposed to have one gasket...... i went to the dealer and asked for the broken one, and the guy says theres a split on which they used in 97.. the dealer that had this apart last, put both in (the other style is a green o-ring)!

before i bought the truck it was ONLY dealer serviced, i know it had the lower intake gaskets done, the PO gave me a ton of paperwork.. also they broke 1 tab off of 2 injector harnesses i didn't even break any, and i ALWAYS break connector tabs..

thats as far as i got.. had classes today. got a few pics of the hat in the manifold.. i have NO CLUE how i got this lucky, theres no way i dropped it in there thru the intake hole either, as the o ring was still in the injector hole. so it bounced up into the manifold, or fell.. left.. lol

 

[Psychopete]

That plastic "hat" shapes the injector spray pattern.

Just FYI, the "hat" is called a penticle cap. Had a parts counter employee going in circles looking for a injector "hat". I eventually found it in a book and said, "Here, this is what I want."

Pete

 

[compleckz]

haha, thanks for the info.. a quick search of auto zone and advance's website.. no leak down tester.. so most likely i cant borrow/rent one from them.. and i don't now anyone with one..

pics of the pentacle cap

my intake is GROSS, is this caused by the EGR/is the EGR bad, or does this normally happen over time?

 

[MAKG]

It can be caused by the PCV system, generally associated with lack of oil changes or other oil problems (perhaps running hot, fouling, or excessive blow-by).

You only need a leakdown tester to test rings. For valves and head gaskets, you only need a spark plug fitting for an air compressor. You don't care how much leakdown there is, because any leakdown is serious.

 

[kunar]

i would bet money that your 'injector hat' popped off when you pulled the injector out. the o-ring stuck in the intake and pulled the hat off. i have had the exact same thing happen to me but it did require some yanking to get it off. and the thing about cutting o-rings....dead serious, make sure you lube them up with a non silicone lube....

 

[compleckz]

It can be caused by the PCV system, generally associated with lack of oil changes or other oil problems (perhaps running hot, fouling, or excessive blow-by).

shitty.. well, i do regular oil changes with mobil 1 (the last 31k miles).. so if its fouling, lack of changes, or overheating oil, i blame the PO

hopefully its not excessive blow-by.

any safe way of cleaning that gunk out without removing the lower intake?

and just regular old vaseline on the new o-rings?

 

[compleckz]

so i replaced the egr tube o-rings, and the injector o-rings.. i couldnt find a leak down tester locally, but i had time today, so i put the truck back together (i swapped the #4 and #5 injectors).. i also disconnected the battery for 10 minutes. started up fine as usual, and it seemed to be running 'ok', no codes.. but then i went around to the exhaust and could definitely tell it was still running rough.. just like before..

no codes after a short drive, some full throttle pulls... cats are still getting hot, and exhaust smells... bad not like eggs, but just abnormal--cant describe it..

so i would almost immediately get a #4 misfire code before... but nothing now.. yet it still runs exactly the same...

for haha's i unplugged the left bank's o2 sensor to see if it ran better or worse.. it ran exactly the same.. and didnt even shoot a code.. just curious to me.

so i guess i'll borrow a compression tester cuz i know a few friends with those.

 

[almostclueless]

Just FYI, the "hat" is called a penticle cap."

A penticle cap, huh? Is that a hat for someone with five gonads?

 

[MAKG]

any safe way of cleaning that gunk out without removing the lower intake?

Not really. Even if there were, you can't reach most of the passsages without removing the lower intake. It's not that serious unless there are solid bits (abraisive) in there.

and just regular old vaseline on the new o-rings?

Yup. Or just about any other kind of grease that won't eat the O-rings. Vaseline works nicely.

 

[compleckz]

so i tested the o2 sensors again, and drivers side i can only get up to .28volts.. the book says it should be between .35v and .55v..

and as i said before unplugging them does not make the truck run any different, whats the deal with that? i unplugged them during running before, and before this time, tested after like 10 minutes of the truck idling..

ALSO for some crazy reason the DPFE left side hose keeps blowing itself off...

also when i unplug that, it dosent make the truck run any differently either.