clunk?

now on to the next problem. i ordered the CPI and should be in 3 days. the other thing i noticed is that when ever i take off in my truck theres a clunk on the driver side. any ideas. only taking off and not around turns. the other thing is that i have a lifter getting stuck that taps untill warm and then goes away. but the bigger problem out of both is that i noticed the other day that if the truck sits all night and then i start it up it sounds like a pistons knocking. u can hear well if you take off with it with out leting it sit for a few mins. it does it in the cold and warm weather but only does it if it sits for a long time. after driving 100 ft or so its gone and you never hear it again. what could be doing this. the motor only has 72,000 miles on it. its a 95 GMC jimmy with the cpi motor. auto tranny.

Sticky lifters.... Ad some Lucus oil stabelizer and that should help it. (unless you wanna pull everything and replace the lifters.

how hard are they to change? i'm already running moboil 1 trun syn oil. 10-W30. that stoped the taps for the most part but the cluck or knock is still there.

You need to pull the heads and lower intake. Then simply pull the old lifters out, put the new ones in. Also add in the new rocker rods while yer at it. The old ones will be worn to the pattern of your existing lifters. It's about a 4 hour job if that.

For the clunk, look to your motor mounts, see if the pad is seperating... Steering box uses a higher gear ratio (same as the iroc z28) so more responsive steering. Next mod up 5.7 MPFI Vortec from an escalade and a fresh paint job.. :) Already bought the motor :) and upgrading my front end to the 98+ style this weekend.

i know the take off clunk could be from there but what about the motor knock/clunk on start up? it never does it when its warm. how much is the enginge upgrade going to cost? once the 4.3 i have blows i'm droping in a 350 and its going to be a race/track truck.

i know the take off clunk could be from there but what about the motor knock/clunk on start up? it never does it when its warm. how much is the enginge upgrade going to cost? once the 4.3 i have blows i'm droping in a 350 and its going to be a race/track truck.

Lemme guess, you are using a Fram oil filter?

i used a fram when i first got it and now i don't use them. i have syn with a hastings oil filter. the part store i get it from is changing over to wicks. don't know if i should get them or a acdelco.

Anything is better than a Fram.

You might want to run an engine flush cycle the next time you change your oil.

It will get rid of the gunk in the oil system which may be hindering the oil getting to where it is needed.

i have a leaking CPI so i think that would clean it out. i'm putting a new one in wednesday.

You should replace the nut kit as well at that age...Save you from opening the plenum again.

i have a leaking CPI so i think that would clean it out. i'm putting a new one in wednesday.

A leaking nut kit will "clean it out"?

Also, follow rlith's advice and replace the nut kit while the plenum cover is off.

Chances are you have some bearing damage from fuel diluting your oil and causing the oil to lose its lubricational properties.

oil pressure has always been normal. the oil doesn't have a strong smell of gas so i don't think its done any damage yet. but i'm going to change the ol any way. i was already going to change the nut kit.

Again, stop talking about it and do it.

You have been saying you are going to be changing it now for about 4 months.

i'm off wednesday so i'll have the time to do it. i'm picking the CPI up monday and then i have to find a nut kit. i don't think the nut kit comes with the CPI. its costing $319. it would be nice but they said they only have what ever comes with the CPI. so i might have to go to the dealer for the nut kit.

The nut kit doesn't come with the CPI, you can get it at the dealer for about $45.00, the CPI you can get at advance autoparts for $270.00

don't have a advance auto thats local. ok. at least i know what to pay for the nut kit. i thought it might be around $100. i'll pick it up tomarrow.

gmpartdirect.com has them too.

picked up the nut kit and the CPI. CPI cost about $342. the nut kit from dealer was $64. i'm putting it in tomarrow. i'm going to follow s10's wedpage on how to do it.

You will also need a new plenum gasket.

You CANNOT just reuse the old one.

what about using sealent on both sides. worse case i'll get one tomarrow. can you tell me what a ping sounds like on a motor?

Only use the plenum gasket, do not use sealant EVER.

Pinging is in most cases undetectable and can only be detected by the knock sensors.

In bad cases it will sound like metallic rattling coming from your engine when you for instance are going up hills.

could a bad CPI make it sound like a knock to the motor on start up? 5-10 mins. once the oil starts flowing? the best way i could tell you is it sounds like a piston knocking. but its only there when its cold. or could the lifters be doing this?

could a bad CPI make it sound like a knock to the motor on start up? 5-10 mins. once the oil starts flowing? the best way i could tell you is it sounds like a piston knocking. but its only there when its cold. or could the lifters be doing this?

Nope, it won't cause that.

What you might be seeing damage caused by racing an engine with fuel laden oil.

The damage might have already been done.

what could have gone bad? it always been there since i got the truck. the person before me never raced it so i don't think thats it. it only does on start up and i think that if something was really gone it would at least do it under stress. could it be carbon build up in cyinders?

What grade of oil are your using?

10-W-30. Mobil 1 true syn. cold ol can get as high as the mark in between 40 and the red line. normal idle is just below middle mark and above 1,000 RPMs is at the middle mark or just past.

Ok, well, for one, what temperatures is your area seeing lately?

Secondly, your engine calls for 5w30. Why you are running 10w30 is beyond me and is probably causing the cold start knocking.

You sure you don't have a Fram oil filter installed?

its in the 30's. it does it in the summer too just not as bad. i'll try to get some 5W30. and yes its not a fram since i won't use one using syn. since they only last about 3 months where i need mine to last 12.

Once you have fixed your CPI and nut kit, I would swap in a new run of oil.

Chances are your oil is really screwed up with gas. You might not smell it, but it is there.

i put in the CPI and checked that there was no leaks. i started it up and the idle was rough. i reset the computer and let it idle for a while and when i came back it smell like rich gas and the SES light wa blinking. i did pull the right side plugs of the cap since it was easy to do the nut kit. could it being out of time cause this? whats the fireing order looking down on the motor? and i let the truck sit for 30 mins with the top off and no leaks so i know thats good. anything elise?

never mind. i had the back right 2 plugs switched. it started right up and had a rough idle but slowly picked up. but then went back but still smother then the first time. the light still blinks? know of some place that has a diagram?

You sure you plugged in all the sensors?

Make sure they are all connected properly.

all pluged in. i even tried unpluging a few to see if it did any thing and it either made it worse or no diff.

Did you switch out the nut kit when you switched out the CPI?

yes. both were replaced. the CPI came with the meltal lock and the 2 o rings. i didn't use them since the nut kit had ones on it. were these extra? should i pull the intake and cheack for leaks?

Can you talk in one thread on this problem, you have two threads going on the same problem and it is getting annoying.