: spark plug gap?



capn
02-29-04, 02:33 PM
Hey all

today i was cleaning my EGR valve and decided to check some other things like belt wear, plugs, etc. but when i got to the plugs i noticed that they were white and very wide, which indicated they have been in thier too long and causing a lean mixture, am i correct?

so im either going to get some delco plugs or regap my existing ones, but i checked in my "chitlins" crap manual and IT DID NOT HAVE THE GAP, so i need to know the gap, and or what are the best plugs to buy

thanks

capn

Lawrence
02-29-04, 02:37 PM
Not sure, and my hood is off right now but.....try looking for a decal under the hood. Tune-up info is usually there. Might try the owners manual as well.

Lawrence
02-29-04, 02:47 PM
I just checked my manual.......not there. According to the Haynes manual (I didn't buy it) it is .050. Buy the AC Delco plugs.

BostonETC97
02-29-04, 07:52 PM
Gap on a '97 ETC is .060, as stated on the under-hood label. I used AC Delco plugs, which were pre-gapped at .035, and needed to be opened up a bit.

Allante North *
02-29-04, 10:06 PM
I gap the Allante North* at .060 as per Service Manual and use AC Delco plugs.

capn
02-29-04, 11:00 PM
Thanks guys really appreciate it

BeelzeBob
03-01-04, 02:28 PM
Hey all

today i was cleaning my EGR valve and decided to check some other things like belt wear, plugs, etc. but when i got to the plugs i noticed that they were white and very wide, which indicated they have been in thier too long and causing a lean mixture, am i correct?

so im either going to get some delco plugs or regap my existing ones, but i checked in my "chitlins" crap manual and IT DID NOT HAVE THE GAP, so i need to know the gap, and or what are the best plugs to buy

thanks

capn

Capn....the plugs should look "wide and white". Spark plugs will not cause the engine to "run lean". The OEM dual platinum plugs will look bone white under normal conditions. They are designed to run that way. No problem. Unleaded fuel does not "color" the plugs the way you might think in the past. Running with good unleaded fuel the plugs will stay pure white. Any colors observed are usually due to additives in the fuel you use.

Look carefully at your plugs and you can see the tiny platinum pad that is on the ground electrode and the center electrode. It is there and should be visible. Plugs of your era were famous for loosing their tiny platinum pads over time and miles. Not all do but some did. Look at each of your plugs carefully. If both of the pads are there, put the plug back in and forget about it. They will run virtually forever as long as the platinum pad is there. If it comes off the plug will start to erode and the gap will open up. The plug will still operate fine...until the gap gets too large. Just replace the plugs with missing pads with new OEM dual platinum plugs and forget about them.

You might also want to consider cleaning the phenolic spacer plates under the intake manifold. The phenolic plates isolate the intake assembly from the cylinder head itself and form/contain the EGR delivery passages to each of the individual intake ports on the 93/94 engines. Yours are probably clogged to some extent with carbon and in need of maintenance by now. Just remove the 4 inner, recessed bolts in the silver top cover of the intake and lift up the intake enough to slide the phenolic plates out. There is one per side, two per engine. Clean out the passages in the plates. Obvious once they are in your hand. Also, clean the small square notch or "mouse hole" machined into the heada surface at each intake port. Clean the EGR delivery port at the rear end of the cylinder head also. There is no coolant or anything in the manifold ports and the seals are reusuable so it is a pretty simple task to lift up the intake enough to get the plates out and clean them. This is what is required for preventive maintenance on the 93/94...not cleaning the EGR valve itself.

capn
03-02-04, 07:02 PM
Capn....the plugs should look "wide and white". Spark plugs will not cause the engine to "run lean". The OEM dual platinum plugs will look bone white under normal conditions. They are designed to run that way. No problem. Unleaded fuel does not "color" the plugs the way you might think in the past. Running with good unleaded fuel the plugs will stay pure white. Any colors observed are usually due to additives in the fuel you use.

Look carefully at your plugs and you can see the tiny platinum pad that is on the ground electrode and the center electrode. It is there and should be visible. Plugs of your era were famous for loosing their tiny platinum pads over time and miles. Not all do but some did. Look at each of your plugs carefully. If both of the pads are there, put the plug back in and forget about it. They will run virtually forever as long as the platinum pad is there. If it comes off the plug will start to erode and the gap will open up. The plug will still operate fine...until the gap gets too large. Just replace the plugs with missing pads with new OEM dual platinum plugs and forget about them.

You might also want to consider cleaning the phenolic spacer plates under the intake manifold. The phenolic plates isolate the intake assembly from the cylinder head itself and form/contain the EGR delivery passages to each of the individual intake ports on the 93/94 engines. Yours are probably clogged to some extent with carbon and in need of maintenance by now. Just remove the 4 inner, recessed bolts in the silver top cover of the intake and lift up the intake enough to slide the phenolic plates out. There is one per side, two per engine. Clean out the passages in the plates. Obvious once they are in your hand. Also, clean the small square notch or "mouse hole" machined into the heada surface at each intake port. Clean the EGR delivery port at the rear end of the cylinder head also. There is no coolant or anything in the manifold ports and the seals are reusuable so it is a pretty simple task to lift up the intake enough to get the plates out and clean them. This is what is required for preventive maintenance on the 93/94...not cleaning the EGR valve itself.

OOOOOOOooo ok but i was throwing a trouble code saying i had impropoer Pintle position on my egr so i figured i would clean it, but good advice

Oh and while im on the topic of egr and such, when i was doing my EGR vavle some of the rubber holders for the vacuum lines were cracking, would anyone know if i can replace these?

BeelzeBob
03-02-04, 11:17 PM
Yea, OK, didn't know about the code. If you had the code for pintle position then cleaning the EGR valve was the correct thing.


I would still do the phenolic plates and mouse holes in the ports as they are likely clogged and need cleaning anyway.

capn
03-03-04, 10:20 PM
do i need like any specialized tools for that? or just basic torx and sockets?

BeelzeBob
03-05-04, 11:32 AM
do i need like any specialized tools for that? or just basic torx and sockets?

I don't think you even need a torx... Just remove the four center, recessed, bolts in the silver top cover and lift the manifold up enough to remove the plates, clean them and reinstall. Clean the mouse hole in the heads at each port while the plates are out. Just leave the manifold in place and block it up several inches with a block of wood. You only have to remove the center 4 bolts not the perimeter row of screws in the silver top cover.

capn
03-05-04, 06:43 PM
I don't think you even need a torx... Just remove the four center, recessed, bolts in the silver top cover and lift the manifold up enough to remove the plates, clean them and reinstall. Clean the mouse hole in the heads at each port while the plates are out. Just leave the manifold in place and block it up several inches with a block of wood. You only have to remove the center 4 bolts not the perimeter row of screws in the silver top cover.
i tried that and it was pretty hard i'll have to do it again