price of a tune up? / shudder at red light

[thedevilleinme]

Hi all.

I've got a shudder/pulse when sitting at red lights that's getting more rhythmic and more frequent. It was just one or two a couple of days ago. That sounds like plugs need changing?

95 concours 137k miles. Haven't changed them yet since I got the car when it was 85k..

How much is a tune up generally? Dealer service shops around here want $600-700 bucks. Pepboys says $200. Any reason not to just go to pepboys? Do dealer service shops have any specific equipment pepboys might not have?

[Playdrv4me]

Its more important just to make sure the right spec parts are used. For example, make sure only A/C Delco genuine spark plug wires are used, even if you have to bring the parts yourself.

[Ranger]

A/C Delco wires from rockauto - $225
A/C Delco 41-950 plugs - $5 ea
Labor (DIY) - $0
Self satisfaction - Priceless

[krimson_cardnal]

Ranger - you have a way of saying it - PRICELESS!!!

Originally Posted by thedevilleinme

Hi all.

How much is a tune up generally? Dealer service shops around here want $600-700 bucks. Pepboys says $200. Any reason not to just go to pepboys? Do dealer service shops have any specific equipment pepboys might not have?

Exactly what do you have in mind when you say tune up? Nothing you couldn't handle... search these forums - make a list. K_C

[chubbyranger]

Shudder at idle often = vacuum leak or plugged PCV valve, I'd start there since its usually the easiest and cheapest fix.

[thedevilleinme]

thanks for the responses, guys.

Originally Posted by krimson_cardnal

Exactly what do you have in mind when you say tune up? Nothing you couldn't handle...

hm.. chicken i guess. have been shocked by my own ineptitude lately. i've changed lightbulbs around the car and the window motor, air filter. just the simple no-risk stuff not related to the actual running of the car. read some on changing plugs and the talk of cross-threading or breaking plugs and dropping bits into the cylinders made me think i should avoid it. i'd have to do it outdoors in some parking lot also. it's really dusty around here. but.. now it sounds tempting..

the dealers say they'd change plugs, wires, check the timing, check the throttle plate (extra charge to clean), oil change, fuel filter i think? i checked with another dealer who wanted $800.

ah.. if i took it to the dealer i think they'd be able to spot any other problems that needed fixing.. while trusting them to be honest on that.. so if it is something else like a vacuum leak or something else i wouldn't know about.. or if there were some other problem i wouldn't know to look for.

Is this the right part # on the wires?
ACDELCO Part # 748J {#12192049}
WIRE KIT,SPLG

i'd need a torque wrench - never used one.
a plug socket for the wrench?

do new plugs need to have the gap adjusted?

if i end up diy-ing - you think this can wait a few days more for the parts to arrive?

[Ranger]

Yes, that is the correct wire number. Rockauto has good prices and fast shipping. No need for a torque wrench. Just snug 'em down good and don't get crazy. Always check the gap on new plugs and adjust if necessary. You WILL need a plug socket and a 6" extension. Do the wires one at a time so you don't screw up the firing order.

[thedevilleinme]

Saw some other threads on this and wanted some confirmation:

It's ok to remove the crossbar going to the strut towers, and the coil packs/icm in order to get to the rear four plugs? pretty awkward reach and pretty dirty - don't want to be knocking gunk in there.

Anti-seize is ok if used very sparingly?

I pulled the boot off one of the plugs to have a look today - there seems to be a little oil (?) sitting in the bottom of the tube where the plug goes into the engine... sign of..? engine wear?

[chubbyranger]

There is another thread here where I recall that it was recommended you not use anti-sieze on AC Delco plugs because they have a special coating. Go by the recommendation of the plug manufacturer. When I changed the plugs on my 99 N* I had to remove the coil packs to get to 3 of the back 4 plugs. There are four 10mm bolts, two of which you can't see but its still not that hard. I had to pull one or two connectors to flip the coil packs out of the way and pull the #3 plug wire off the coil to get to one of the coil pack bolts. Fortunately the coil packs and wires are all numbered on my car - check that first before you pull anything, otherwise use tape or some kind of marker to label before you move stuff.

[Ranger]

The oil in the plug wells is just seepage from the "O" ring seals in the cam cover. Pretty normal and nothing to be concerned about. Just soak it up as best as you can.

[thedevilleinme]

is it safe to use WD-40 to loosen a stuck plug? the guys at autozone recommended that when i asked for penetrating oil (they hadn't seemed to have heard of that).

i started doing this yesterday - i've been cleaning stuff around the area and waiting for a sunny low-dust day to actually start.. i unmounted the coil packs to get to the back four plugs. then some guys showed up and started cutting granite countertops next to my car. i left everything sitting, control cables unplugged from the icm on both sides, grounding (?) cable unplugged from icm. about 6 hours later when i plugged everything back in the car started but shuddered rhythmically. i shut it off and went to bed.

then this morning - it turned over but won't stay running.

normal?

I went ahead and started changing plugs and wires. I've gotten to three of them in the front so far. the plugs are pretty dirty around the threads and look kind of burnt.

Then I ran into a stuck plug. (front one nearest the oil cap).

Does this all seem normal? WD-40?

[thedevilleinme]

was i supposed to unhook the battery before starting all this?

oh yeah - i changed the pcv valve earlier this week. thanks chubbyranger. that actually seemed to help. i still got some shuddering but it seemed to improve. or maybe it was because i'd been fiddling with the plug wires?

the rubber elbow holding the valve cracked when i pulled it out so i changed that too.

[chubbyranger]

You shouldn't need to disconnect the battery to do plugs. I've also never used penetrating oil on a spark plug - eventually they come out but its a real gut check when you're cranking on it. I prefer socket operator lubricant The rythmic shuddering could be a misfiring plug or plugs because they're shot or bad wires causing the plugs to misfire. Could also be a bad distributor cap - the rythmic part leads me to believe that its plug related instead of something else.

[thedevilleinme]

thanks. i was afraid i'd drained some volts or something..

ok. so i was able to change 7 out of 8 plugs. #2 still won't budge (closest to oil cap). it took me from early afternoon to after sundown. finished by flashlight. my back is a little tweaked and knees too. probably from leaning forward but trying not to fall in. yeah - i considered a drinkable additive after a couple hours too. haha.

i was pretty worried about cross threading - some of the plugs came out only with a lot of coaxing back and forth and squeaking metal on metal sounds. unnerving to say the least. some of them were very burnt looking or dirty - if i could do over, i'd have made a map and more detailed notes on the condition of the stuff i removed. here's what i managed:

#3 was filthy and difficult to remove - it had a lot of sticky clotted brown gunk on the threads. i couldn't use the unscrew-with-a-length-of-tubing method on this or the other tight ones and had to work them back and forth and use pressure with the wrench..

#5 and #7 were difficult to get out and seemed rusted or dirty - carbon-ed? they squeaked a lot when i took em out and put the new ones in - these are the ones i was afraid i was cross threading. it seems like the threads were so dirty they were keeping the new plugs from going in.

what do people use to clean threads on the engine? i just put the new ones in and if they didn't go in i backed them out, cleaned the plug threads with a paper towel or a wooden toothpick worked good - and then put them back in. should i have tried to clean up more? ...

i ended up unmounting the icm and resting it on top of the engine on some newspaper. i tried to get the cables routed the same way but managed to drop one of the plastic clips that holds three of the wires for the back four. it fell to the bottom somewhere with a tinkling sound but didn't come out on the ground.. then i snapped the two wire clip that holds the #7 (?) to the #5 wire. the new wires overall seemed a tiny bit shorter than the old ones. normal?

i read somewhere else here there's a risk of crossfiring if things aren't routed exact as factory. how exact are we talking? i tried to keep things the same but things got a little messy when i got to the back plugs.. i'll try to pick up a replacement for that clip - it was the one that holds three wires - i think for #1, 3, 5.

a couple of the old wires and electrodes at the coil packs were badly.. corroded? one looked rusty when i took the wire off, another was completely black and drained black powder when i took it off. i wire brushed it a little before greasing it up.

i left #2 unchanged with the boot hanging out - didn't want to pull on it more than necessary. i'll try again in the morning. had to eat. and sleep.

[thedevilleinme]

one other thought..

i'm a little concerned that the car didn't start this morning after i had poked around the wires yesterday. and also that the old plugs were so dirty. it's sinking in that this is likely the first change after nearly 140k. i regret that..



is this level of filth acceptable..? or do i need to take more steps now beyond changing plugs and wires.


if one or two of the plugs or wires were shot - and supposing i further messed them up while poking around - does it cause the car to not start?

kind of the same note, is it ok to leave the one bad plug in temporarily and drive to work in the morning? it seems like plug wires are considered so fragile i don't want to pull them on and off too much..

ok. two other thoughts. thanks guys. hope this is all just worry-warting..