Missing... but it sounds meaner... :P

[PlatinumZ34]

Well the 3.4 is missing. New plugs, cleaned injectors, old wires (although they look new, i haven't replaced them so they're at least a year old), old coils. One day when i was boosting my buddies car, out of the top 3 things that look like coils (over the rear bank of spark plugs on the driver side) one of those was smoking. I know the coils are under the exhaust manifold so i dont know what these upper things are...

My SES light is on and my low battery light is on, my alternator is putting out 14.7 Volts so its not that even though it sounds like its bad, it sounds like i have a supercharger . brand new battery as well.

The only thing i dont get, is it seems to idle fine off and on, it stalls once in a while since i have the original injectors which are faulty apparently, but other than that it usually idles nice and smooth at around 900 (ya its high i dont know why). Then it idles like its missing, and i have noticed a decrease in power, but i also took off my SR intake, which i dont think would make that much of a differance. Everyone who gets in my car says "sounds like its missing" and then at WOT "it sounds alot meaner now"... and it does, it has a much much dirtier sound.

The back drivers side plug is always covered in oil, somethings leaking back there (not alot, but enough for the plug to be covered in oil when i pull it up) so it could be that too i guess.

Any ideas?

(1991 5 speed, 315 000 km (ya i know))

NGK g-power (i think, super tiny platinum tip) spark plugs, with no more than 5000km on them.

I haven't gotten a chance to start replacing stuff and checking all the plugs and wires since its currently blizzarding and the '47 and explorer are currently in the garage right now. I dont think the Z will make it out of the driveway actually haha, probably only 2-3-5 inches of snow, but some drifts are quite a bit higher (8-9 inches, some areas its a foot high already), my friend got stuck in front of my house and his car is higher than mine.

[RednBlack]

That would be your EGR solenoids. The 3 coil things. I would also assume that you have a valve cover leak into the plug hole. From there,...who knows. EGR solenoids need replaced as a start.

[Lyle's GTP]

The "super tiny platinum tip" could be an Iridium plug.

Here's the link. http://www.ngkspark.com.au/feature_product.html

Lyle

[PlatinumZ34]

i wish they were iridium haha but no they're these:

http://www.ngksparkplugs.com/products/cars_trucks_suvs/gpower.asp

how much do these EGR gizmo's go for, and ya i'v ebeen told its my valve cover, but i think that'd be a lot of work for how little its leaking, i dont THINK it would have ruined my plugs/connection etc.

the EGR thing only smoked once that i've ever seen, and that could have been the oil leaking from the valve cover burning, but it wasn't blue smoke...

[Lyle's GTP]

Well, you shut me up.

Lyle

[blk92z34getrag]

You might have a vaccuum leak, which would explain the missing / loudness. Start your engine, and spray carb cleaner on the intake manifold to see if it makes the engine studder.

If your EGR valve is out, good luck. Mine was over $200 (can't think of the exact price now, 238 or something). Real easy to replace, but if you don't get a GM replacement (I didn't) you have to cut your own gasket (pain in the ass).

Now, is it an actual "miss' or is it more of a "put-put" that's happening? If it's missing it will be consistant every single revolution, the put put is more erratic.

If it's an actual miss, check the plug wires near the exhaust manifolds, I had one of mine fucking melt on to the exhaust manifold about a year and a half ago... that was when I learned how to correctly route the wires... also what you can do (my dad suggested this and it's how I found my short) run the engine when it's dark outside (real dark, no lights anywhere) unplug the underhood light, and check to see if you see any arcing anywhere.

[manny]

If its your EGR valve it should throw a code. 3.4's do idle higher than 3.1's 900 isn't that odd. You can get EGR valve gaskets from your local part store now. They have pressed metal gaskets just like exhaust manifold gaskets. Our cars require two, one on the EGR valve and one on the spacer.

You've got the three solenoid digtial EGR, you can test it yourself. Visit your local J/Y and get an extra four wire harness from the middle of an EGR valve (get about 3" of wire). One of the brown wires is a ground. Test the leads on a 9v battery, you will hear a click if the solenoid is working. That's also how I test them at the J/Y before I buy, so I get a good one. I got one for about $15.00. Yours may just need cleaning. Sometimes the carbon buildup inside of the valve prevents one of the pintles from closing, giving you a small EGR flow at idle. Sometimes the EGR gaskets cause a vacuum leak too.

[PlatinumZ34]

Ok well its more of a put put then a full out miss. And today my car decided to stall and then not start, it wasn't getting gas. I WAS on empty, but after a few minutes i got it to start again and got to the gas station. This plus the stalling every few red lights is making me say injectors... Im thinking the injectors are definately needing a change, cleaning them didn't do anything (waste of money :@)...

Other than that ill check for intake leaks, and ya im sure i have a few vaccuum leaks, my dad was driving and said the way the brakes felt made him think vaccuum leak.

ALSO i just noticed today on my number 5 plug wire, theres a little chunk taken out of the insulation, i think it could be all the way down to the metal, new plug wires say you??? if so say you yay to magnacore??? worth the extra money, and how much extra???

Screw EGR, ill just get ben's chip if its gonna be 200+ bucks. i realise this is a bad idea in winter...

[SappySE107]

If the brakes feel bad, check the brake booster hose and the check valve that it attaches to.

Why is it bad to have the EGR off in the winter?

[blk92z34getrag]

You have a 5 speed, I just noticed that.

If your car stalls, and won't start up again. Try this. Floor the gas, and then start the car. I think it forces the computer into a different start-fueling procedure... I forget what it's called but I know it will start the car if it refuses to start. I have to do it occasionally. The chip definately helps the stalling though. It's worth it in the incresed driveability and the performance.

If you're gonna get new injectors, get them off of a 97 LQ1. Supposedly they should cure the idle problem. I'm buying a set in a few weeks and I'll let you know, unless you get a set before me.

[PlatinumZ34]

alright thx, ya I guess theres another reason added to my list for getting the chip... this is probably going to be a very dumb question, but how would one install one of those gizmos...

and doesn't the EGR reuse gas and such from the engine and a small amount of exhaust, thereby increasing the running temperature when its cold?? I know im not right, but i think im close... unless im way off.

[blk92z34getrag]

The EGR just recirculates the exhaust gas from the exhaust manifold to the intake. Hance its name Exhaust Gas Recirculation Valve. It works under part throttle conditions to heat up the intake air, thus reducing the emissions.

And as for the chip, it's easy. It's on the left side of the engine compartment. Take off the coolant overflow bottle, take off the cross-brace there, then unbolt the fuse block, and there will be a black box under it with a whole shit-load of wires running into it. I think there is a bolt holding it to the fender, you remove it, and there will be alittle panel you have to unscrew. There are like 6 1/4" bolts holding it down, the chip is inside.

[PlatinumZ34]

ok cool, ya i've seen that little box before... don't ask how, but lets just say if you want to turn off your fuel pump your best bet is just to go straight to the wire on the fuel tank or w/e... cauase the fuel pump relays dont do anything ...

So im just wondering, would it hurt to have the EGR off in -40 weather? (which is what we experiance every year...) and also will i lose gas mileage and such?

[napatiger]

How did you clean your injectors? Just with a bottle of Fuel Inj Cleaner from an autoparts store, or did you send it to witchhunter.com for a professional cleaning/balance?

[PlatinumZ34]

used a bottle of inj cleaner and then hooked it up to the machine thingy