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350rs
05-18-2010, 06:12 PM
Unbelievable..

Finally have idle problem solved and all was FINALLY running well with the car. First time since shortly after i bought it. And now i throw code P0300. Using search i found that the NGK Iridium plugs have been known to mess with these cars. But ive had them in there 15k miles or more.. I guess all i can do is pull them and check them out, replace maybe. Ill check the boots. One coil pack is brand new but i still have the old one. Maybe it went bad somehow?

Was fine on the way to work. On the way home however.. I had to hammer it to get past a super slow lady on the highway. Only went from 55 or so to 70 or 75 but i think thats what did me in. Ran fine the rest of the way on the highway. As soon as i got off and to a complete stop though heavy shaking from the misfire. Had to get home though and i was still 15 mins away. I made it home and messed with it a few seconds before shutting it off. It runs better but not great in neutral or park ( no load ).

What is MOST COMMONLY the issue here? Ill check what can be checked shortly. How often do these cars jump a tooth on the timing chain? With the RPM's and whatnot i about half expect that issue. But i dont at the same time since it runs fine at speed.

350rs
05-18-2010, 08:22 PM
checked all plugs and wires. two looked fishy ( from the same coil that i just replaced) so i replaced them. Now i have it down to ONE cylinder at least. Cylinder three. But this scares me. The two i replaced looked to have a lot of rust of them. All of them seemed to have some. And two of the cylinders are right beside each other.. AND i noticed im loosing coolant. But not externally and its not mixing with oil. I dont notice any white smoke. but that dont mean its not a small enough leak that i dont notice the smoke. So, possible head gasket job comming up.

350rs
05-19-2010, 01:21 PM
well due to all problems im having.. im pulling the motor. Ive got several leaks anyway. Worth my time to take pics and make a walk through? IMO if you need one you shouldnt do it.. but some people are just bound and determined.

AaronGTR
05-19-2010, 05:23 PM
just fyi, I've never had any problems with NGK iridium plugs or heard of them causing misfires. They wouldn't be fine for 15k miles then just suddenly cause a misfire problem to pop up that is severe enough to set a code in the PCM. There has got to be some other issue.

350rs
05-19-2010, 08:34 PM
there is. head gaskets causeing them to foul. but none the less i found a few threads stating that they had trouble with them.

stewartfn18
05-19-2010, 08:57 PM
how would a hg cause a spark plug to foul. please explain. since ive:
a. never heard of this happening, and
b. never heard of the iridium plugs causing problems on the 3400.

i have them and have had no problems with them.

GrandAmGT-2008
05-19-2010, 09:14 PM
a head gasket pumping too much oil/antifreeze would be enough to foul a plug.. i would think the head gasket would be a bigger issue than a fouled plug though.. imo

stewartfn18
05-19-2010, 09:23 PM
a head gasket pumping too much oil/antifreeze would be enough to foul a plug.. i would think the head gasket would be a bigger issue than a fouled plug though.. imo

ok ummm, unless the hg failed coolant and oil should NOT be in the combustion chamber AT ALL. ignorance is bliss. good god. fouled plugs are usually caused by the car running too"rich", do i need to explain to u what running rich is??

GrandAmGT-2008
05-19-2010, 09:37 PM
then where is his coolant going genius? and yeah what is rich? do you mean there is too much fuel and not enough air? crazy..

stewartfn18
05-19-2010, 09:41 PM
then where is his coolant going genius? and yeah what is rich? do you mean there is too much fuel and not enough air? crazy..

coolant does not go into the cc. it circulates through passages in the block. good lord do i need to school u again or are u going to drop this e thug thing u got going, and y do u need to resort to name calling. are you 12?

GrandAmGT-2008
05-19-2010, 09:46 PM
you basically called me ignorant.. Your also telling me that there is no way that a head gasket could be blown out between the combustion chamber and a coolant passage.. or that it runs in the lower intake.. could be leaking from a coolant passage to an intake runner too. either way... a head gasket is a possibility... maybe he should do a leak down test on the coolant system, and/or the cylinders.

stewartfn18
05-19-2010, 09:48 PM
ok ummm, unless the hg failed coolant and oil should NOT be in the combustion chamber AT ALL. ignorance is bliss. good god. fouled plugs are usually caused by the car running too"rich", do i need to explain to u what running rich is??

as you can see, i DID say that if the hg failed coolant could "possibly" enter the cc. OP never stated that that was the problem though

stewartfn18
05-19-2010, 09:50 PM
OP do a compression test and youll get ur answer, we cant diagnose your problem, thats up to u. all we can do is point u in the right direction

avro206
05-19-2010, 11:00 PM
Had the same thing on wifes 3400 powered Olds minivan. Had the code cleared, never came back. Maybe it's bad gas?

Guess I was lucky. Read this

http://www.obd-codes.com/p0300

350rs
05-19-2010, 11:14 PM
a head gasket failure can cause coolant to enter my combustion chamber. causing the small amounts of rust im seeing. Which would also explain my nearly empty tank.

Planned on doing a compression test before ripping motor out. I have a small puddle under the TB again which could be the LIM again OR the head gaskets. But this isnt nearly enough mess to cause all of that to leak out in less than a week. Its been starting rough also.

The thing with the plugs was found on this site using the search function. Look or dont look, i found it in several older posts two or three pages back.

Im not here to start the apparent pissing match that has occurred.

edit: its not just any iridium. its the NGK IX or something like that ( which im using ) that have been the problem.

AaronGTR
05-20-2010, 06:57 PM
A head gasket failure could cause you to be burning coolant and could foul a plug. That would be the result of the head gasket failure though of course and would not be a sign that there is anything wrong with iridium plugs or NGK's.... any plug will foul under those conditions no matter what type or brand.

If you had a blown head gasket, you'd know it for sure. If you are getting coolant under the Tb, it most likely is not the head gasket but rather the LIM gasket or something else in that area. There are a lot of coolant connections there.


For your previous question about the timing chain, they usually don't jump a tooth... if they jump they come right off the sprocket and you are gonna bend some valves at the least. It is common for the stock chains to stretch out a bit, and they might jump or break if you push them. That is why most performance builds people go to the beefier early timing set. The stock chain is only really likely to jump off if you are doing something stupid though. Like that guy from california with the built engine and turbo who was revving his motor to 7,000 rpm, after we told him not to.

stewartfn18
05-20-2010, 07:13 PM
For your previous question about the timing chain, they usually don't jump a tooth... if they jump they come right off the sprocket and you are gonna bend some valves at the least. It is common for the stock chains to stretch out a bit, and they might jump or break if you push them. That is why most performance builds people go to the beefier early timing set.

i wish i wouldve known this when i built my motor

350rs
05-20-2010, 10:27 PM
For your previous question about the timing chain, they usually don't jump a tooth... if they jump they come right off the sprocket and you are gonna bend some valves at the least. It is common for the stock chains to stretch out a bit, and they might jump or break if you push them. That is why most performance builds people go to the beefier early timing set. The stock chain is only really likely to jump off if you are doing something stupid though. Like that guy from california with the built engine and turbo who was revving his motor to 7,000 rpm, after we told him not to.

which set is that? Im about a hour or so away from having the motor out and i planned on replacing the chain at least if its getting close to the stretch limit.

When i pulled the radiator hosed ( couldnt get the pet**** lose) i had a strange thing happen. The lower hose was pretty normal. However the upper had the milky oil looking stuff. But when i drained my oil it was clean even for almost 3000 miles. So there is some kind of leaking somewhere. Maybe even in a few places. Ill be getting the radiator cleaned and flushed while im at this stage. Im hoping i can find one of those little comb like things to straighten the fins out on the radiator. Its pretty messed up on the bottom.

Considering replacing the torque converter as well. I have the also typical 2 or 300 RPM jump in overdrive. Has anybody come up with a deffinate fix? Ive heard of a seal on some main shaft leaking, ive heard the TC, the TCC.. anything that is solidly it?

stewartfn18
05-20-2010, 10:32 PM
alot of times people use the 99 3400 timing set

350rs
05-20-2010, 10:46 PM
can i use just the chain? or do i need the whole setup?

350rs
05-20-2010, 10:50 PM
oh btw.. heres some pics. Dond mind the crap floating in the coolant. the bucket wasnt clean. But since most of the coolant is less than 2 months old. it looks REALLY crappy to me. Cant wait to get those heads off.. should be interesting.

AaronGTR
05-20-2010, 11:24 PM
i wish i wouldve known this when i built my motor

hehe, me too. I didn't know about it either back when I did my cam. My chain had some slack in it, just from a stock cam with LS1 valve springs and around 35k miles on it, so I replaced it with a new stock 2000 chain and damper.

can i use just the chain? or do i need the whole setup?

Nope, you need the chain and both sprockets, for the crank and the cam. It's because the chain is wider than the newer one. They used to make it stronger, then decided it didn't need to be that strong and made it thinner for efficiency. :rolleyes: Probably the same reason they used weak stock valve springs.

Anyway iirc it's the timing set from like 1995-1999. Don't remember exactly, the info's on here somewhere though.

Mac0083
05-21-2010, 03:31 AM
you mean for once i got lucky and there's a part on my '99 that wasn't revised and made better for 2000? (for example, 99 UIM vs. +2000)

does this mean i can go ahead and rev my engine to 7000 rpm?

Mac0083
05-21-2010, 03:32 AM
you mean for once i got lucky and there's a part on my '99 that wasn't revised and made better for 2000? (for example, 99 UIM vs. +2000)

does this mean i can go ahead and rev my engine to 7000 rpm?

350rs
05-21-2010, 07:51 AM
Nope, you need the chain and both sprockets, for the crank and the cam. It's because the chain is wider than the newer one. They used to make it stronger, then decided it didn't need to be that strong and made it thinner for efficiency. :rolleyes: Probably the same reason they used weak stock valve springs.

Anyway iirc it's the timing set from like 1995-1999. Don't remember exactly, the info's on here somewhere though.

ok ill look into it. If my heads are warped to the point that they cannot be fixed ( dont see that being the problem but preparing for the worst), can i get heads off any 3400 FWD model? OR do i need to stick to a certain model year. Dont care about performance i want reliability. They will be sent off to the machine shop early next week and be checked. With luck i can get the surface ground and have them grind the valves and be done with it. Might as well do the valve stem seals while im there too.

Any cheap/free things i can do to make this motor more reliable while its out? Or things to check that commonly go wrong? I dont plan on taking the bottom end apart. Ill pull the caps and check for scaring on the crank to be sure.

AaronGTR
05-21-2010, 05:38 PM
ok ill look into it. If my heads are warped to the point that they cannot be fixed ( dont see that being the problem but preparing for the worst), can i get heads off any 3400 FWD model? OR do i need to stick to a certain model year. Dont care about performance i want reliability. They will be sent off to the machine shop early next week and be checked. With luck i can get the surface ground and have them grind the valves and be done with it. Might as well do the valve stem seals while im there too.

Any cheap/free things i can do to make this motor more reliable while its out? Or things to check that commonly go wrong? I dont plan on taking the bottom end apart. Ill pull the caps and check for scaring on the crank to be sure.


Well hopefully you don't have to get new heads. If you do, pretty much any year 3400 will do. Or you could do 3500 head and LIM with 3400 UIM if you where gonna go that far. Otherwise if you stay with 3400 stuff, just make sure to get everything that comes with it. They changed the diameter of the valve guides mid-2000 so if you are using different springs and valve seals you'd need new valve seals, but if you are still using stock seals they'll work fine since that are part of the spring seat and not mounted on the guide. '03 I believe they changed the size of the rocker bolt from 10mm to 8mm, so of course you need the complete rocker set along with the heads if you buy '03+ heads. Same with 3500 heads, need the rockers, springs, etc. That should be pretty much all.

350rs
05-22-2010, 09:07 AM
right on. should be out today and ill let yall know whats up

350rs
05-22-2010, 12:41 PM
Got everything loose and ready to rock. Taking one last break before getting bolts to tranny put. How many are there? About 33??? Why so damn many!?!?

Those flywheel bolts are a trick alone. Had to use a tie down strap to make it all work. ill post a pic of my redneck engineering when i get it off my phone to a computer to upload it.

350rs
05-22-2010, 04:20 PM
mission status: FAIL! several bloody knuckles and 5 hours later i havent managed much. Ive got three of the bolts out i see at least one more.. im sure there are at least two though. Im going to look for a pattern somewhere..

But i do know now 100% that this is a replacement motor. So its impossible to say how many miles are on it. man this sucks.

350rs
05-22-2010, 04:26 PM
according to this website: http://www.google.com/imgres?imgurl=http://members.shaw.ca/betterthanyoutoo/bellhousing/Chevy_BP.gif&imgrefurl=http://members.shaw.ca/betterthanyoutoo/bellhousing/gm_bellhousing_bolt_patterns.htm&usg=__PUKvuIzKZHRW3SL1r1GrId2lrWs=&h=346&w=462&sz=7&hl=en&start=11&um=1&itbs=1&tbnid=M8hoS20nqNafcM:&tbnh=96&tbnw=128&prev=/images%3Fq%3D3400%2Bbolt%2Bpattern%26um%3D1%26hl%3 Den%26safe%3Doff%26sa%3DN%26tbs%3Disch:1

it shares the same pattern as the standard SBC that im more accustomed to. Unless i read it wrong. its somewhat confusing. But it looks like i have 6 of them. Four down, two to go.:doh:

350rs
05-22-2010, 09:53 PM
as for that bolt pattern. totally different. and i discovered that GM LOVES to hide stuff on ya... about 54 mounts and 387 bolts. Including one that tricks you into thinking its not even there. It goes 180 degrees from the others. im sure some of you know which one im talking about. The motor is out now though. Took about 8 hours in total.. what a mess.

AaronGTR
05-23-2010, 09:43 AM
Yeah, it's not a fast process at all. Gotta plan on a whole day when you are pulling a motor.

350rs
05-23-2010, 11:29 AM
pulled the motor out of the camaro in about 4 hours. this one was a pita.

Considering doing the rings.. most likely will not. All depends on the condition of the block. Might be a complete rebuild with machining to the block even. Didnt notice any smoke so i shouldnt have any leakage as far as the rings are concerned.

Tearing down motor in about 30 mins or so. gotta get something to keep the pushrods and rockers where they belong. Maybe ill make a 12 egg omelet. lol Which pushrod is the longer one? Exhaust or intake? Considering just throwing the rods and rockers in a bag for each cylinder.

350rs
05-23-2010, 05:29 PM
looks great inside. Its apparently a semi fresh rebuild as i can see hatching on the cylinder walls still. At least the bottom end is A-ok. Really obvious failure points on head gaskets though. one cylinder was leaking almost all the way around. and two or three others were iffy. Inside the water jackets are nasty though. Gonna have to spend some time washing all that out. Cam looks ok. Going to pull off a cap or two on the crank and big ends of the rod. They should be fine, but just in case. Get this.. my exhaust studs? They came right out!! Only one gave me some trouble and a few taps with a hammer and some penetrating lube made it come right out as well. Timing cover was still well sealed. but that main seal was indeed leaking pretty bad.

My exhaust valves looked terrible on the same cylinders that were iffy. So this may have been going on awhile. It looks like mostly just buildup so i shouldnt have to have them replaced.

Am i going to have to do the crank position relearn or am i gonna be alright?




Im thinking i should go ahead and do the 3800 swap....... HA! j/k

Azazel
05-23-2010, 10:39 PM
How crucial is getting the rockers back on in the right order..... I had a little mishap with my dog and now i don't know which one goes where..... Am i totally f'ed and should just buy new rockers and rods or what? I'm not looking forward to you telling me buy new.....

350rs
05-24-2010, 07:58 AM
dont quote me on it. but im fairly certain that you will have to buy new if you have totally lost track of where they all go.

AaronGTR
05-24-2010, 04:38 PM
If they did a rebuild and the rest of the motor looks good, but the head gaskets had obvious failures... it's possible they re-used the head bolts. If you have head studs, they can be re-used, but head bolts are supposed to be replaced EVERY time you pull the heads. Also they might just not have torqued them properly.

For the push rods, the exhaust one is the longer one and intake is shorter. It does NOT matter if they go back in the exact same spot they came out of, as long as you put the exhaust and intake length rods back in the correct spot. You can look at the valves and ports and tell which are intake and exhaust, it's fairly easy to see. Same with the rockers themselves... they are all the same, doesn't matter which spot they go.

That's the beauty of self adjusting/self aligning rockers and hydraulic lifters... there is hardly any wear on them so they don't really "wear in" to a spot.

350rs
05-24-2010, 05:51 PM
heads are at shop now. should call tomorrow and let me know the status. Anybody using the 99 timing set? Im worried about rubbing/fitment on the cam and crank. I would assume all would work. but i dont know 100% so im not buying anything until i do.

Bolts were pretty tight, but thats not to say they werent overly tight or something.

Im considering painting the UIM to match the black and red "ram air" plastic on the front. Anybody had any luck with rattle can spray? I can get the high heat engine stuff up the road.

AaronGTR
05-24-2010, 07:48 PM
Everything on the '99 timing set will fit on your current crank/cam and fit under the timing cover with no modifications or issues. There are plenty of people on 60v6.com using that set on later year 3400's.

350rs
05-24-2010, 09:16 PM
alright. Wonder why they changed them? Either way thats what i will use. Half the price for a better chain? DEAL!

AaronGTR
05-25-2010, 04:18 PM
alright. Wonder why they changed them? Either way thats what i will use. Half the price for a better chain? DEAL!


Uh, where do you get half price from? The 97-99 chain is $46.96 on GMPD and the 00-04 chain is $47.88. Pretty close on price for the cam gear and crank gear too, and remember you need to replace both of those with the 97-99 parts.


They changed them because they decided the chain on there was too thick for the mild cam and valve springs that the stock motor was using and they could save some friction and weight by switching to a thinner chain and gain some efficiency. Never mind that it stretches and gets slack in it after some miles. :rolleyes:

350rs
05-25-2010, 05:09 PM
Really? Oreilly has the 99 for 47 bucks with tax and the 01 was 97 before tax.

Never ordered from GMPD, how fast is shipping there? I do like the prices.

AaronGTR
05-25-2010, 10:06 PM
Shipping is medium... not real fast, but I usually have stuff within a week. Their shipping prices add a little to the price too which sucks, but if you are looking for OEM parts and not generic replacement stuff, they are by far the cheapest around. They are the only online retailer who sells wholesale price to the public.

350rs
05-27-2010, 08:07 AM
motor is together and ready to go in tonight. Hopefully it will be running tomorrow night. I only get a few hours a night to work on it. That dipstick tube is indeed a one piece deal.. lol. But the dealer happened to have one in stock and it was only 15 bucks! So i should be set shortly.

350rs
05-27-2010, 10:35 PM
Motor is back in. Got two more bolts from tranny to motor and those three on the tranny locator deal. But its held in by its own self now. No pickers, no nothing. Should be running again friday night, or maybe saturday morning.

juanvan
05-28-2010, 10:56 AM
Good job on getting this fix so fast!

350rs
05-28-2010, 12:28 PM
been a lot of long nights. work 8-5 then work on the car from 6 to 10. Takes me a hour to get home thanks to traffic. 15 mins in the morning.

350rs
05-29-2010, 02:43 PM
Its in, running, and 100% done. Leak free and purring like a kitten. Took it for a drive and its hovering around 200 degrees and its about 90 or so out today. Shifts better too. I hope all that work actually fixed all of my problems.

AaronGTR
05-30-2010, 09:38 AM
Awesome man! Good job.