Please help!! I love my car!!

I have a 1982 Malibu that is my baby. She's got a 3.8 liter 229 with a 2 barrel carb. All of the sudden, the engine starts backfiring through the carb and sputtering while I'm driving. The engine idles rough, reving up and down. So, I replaced the spark plugs, wires cap and rotor. Being sure not to get the wires crossed. I changed the oil, oxygen sensor, air filter, fuel filter and the fuel pump. By now I'm pretty tired. So I give it a try...... Still the exact same problem. Oh, did I mention the engine continues to run for like 5 minutes after I turn off the key? She sure wants to run !! Oh and when I get to like gear 2 or 3 of the automatic transmission, the engine boggs down and run really low in gear. Like when you shift from 1st to 4th gear in a manual.
Any ways, I decide to go all out and check the timing chain. Sure had a lot of slack in it. Very loose. This has to be it!! Nope.......still sounds like a helicopter.......poor girl. Someone help her please!

I have a 1982 Malibu that is my baby. She's got a 3.8 liter 229 with a 2 barrel carb. All of the sudden, the engine starts backfiring through the carb and sputtering while I'm driving. The engine idles rough, reving up and down. So, I replaced the spark plugs, wires cap and rotor. Being sure not to get the wires crossed. I changed the oil, oxygen sensor, air filter, fuel filter and the fuel pump. By now I'm pretty tired. So I give it a try...... Still the exact same problem. Oh, did I mention the engine continues to run for like 5 minutes after I turn off the key? She sure wants to run !! Oh and when I get to like gear 2 or 3 of the automatic transmission, the engine boggs down and run really low in gear. Like when you shift from 1st to 4th gear in a manual.
Any ways, I decide to go all out and check the timing chain. Sure had a lot of slack in it. Very loose. This has to be it!! Nope.......still sounds like a helicopter.......poor girl. Someone help her please!

Here's your Rx - Replace cam and lifters, take two aspirins and call me in the morning.

I agree, sounds like a wiped cam.

Any other possibilities? I really hate the fact that I could've replaced the cam while I had the timing chain off. Arrrrggg!!!!!! Thanks a lot for your suggestions. This has always been a very helpful forum.

if it isnt a wiped cam, check the valves, an exhaust valve most likely if it is blowing out through the carb. Pull valve cover, pull the coil wire so it wont fire and turn the motor over. Check to see if you have "rocking" action on all valves. If a rocker arm isnt moving, check for a broken valve, bent pushrod or a possible collapsed lifter. If those do not appear damaged with the exception of the lifter because you cant see if a lifter is colapsed unless you can see the cam lobe movement, its the cam.

Any other possibilities? I really hate the fact that I could've replaced the cam while I had the timing chain off. Arrrrggg!!!!!! Thanks a lot for your suggestions. This has always been a very helpful forum.

Could be a vacuum leak. Check all vacuum lines. I've had 3 229 engines over the years - aside from the fact that all three were 229 cid, had DualJet carbs, and were painted in the GM Corporate Blue paint, the one thing all three had in common were bad cams. All three of them. So, that's my first guess.

OK, on to replacing that cam - but wait.......now the disributor won't pull out. Any tricks on how to get out a stuck distributor? It should pull staight out, right? C'mon ! This is all I need!!!

Spray some PB Blaster on the distrinutor and let it soak a little. The distributor will pull strait out. A broken or weak valve spring will do the same, although I believe your cam is bad.
http://www.pbblaster.com/

Is your idle solenoid working or is the idle set with the throttle stop screw?

My guess would be a plugged catalytic converter. Really screws things up.

^ yeah, it may be a bad cat.

My guess would be a plugged catalytic converter. Really screws things up.

That's not going to make a big difference at idle or low speeds. Where you see a failed or plugged cat is at higher speeds - power falls off and the engine temp climbs.

So, how do I know if the cam is bad? I've got it out and it doesn't look worn. The lifters are still flat and look pretty good. Maybe I should just shut up and replace it, then see what happens. But what if thats not it?

No........SHUT UP!!! THIS HAS TO BE THE LAST OF THIS MADNESS!!!!

So, how do I know if the cam is bad? I've got it out and it doesn't look worn. The lifters are still flat and look pretty good. Maybe I should just shut up and replace it, then see what happens. But what if thats not it?

No........SHUT UP!!! THIS HAS TO BE THE LAST OF THIS MADNESS!!!!

If you've got the cam, replace it. Usually, a worn lobe will look a little more broad than the others. In the engine, the rocker arm associated with that lobe will barely move, or it will move less than the others. Worn lobes also tend to have a "rough" look to them, pitting etc. The lifters will often, but not always, wear in a concave pattern on the affected lobes. I've seen one so bad that it was worn into the oil cavity inside the lifter, resulting in about a 1/8" hole in the bottom of the lifter.

If you didn't mark the exact cylinder and valve each lifter is for when you pulled it out, you will be replacing your cam and lifters anyway.

I check pushrod travel with a dial indicator set up, which I know everyone doesn't have, maybe you can borrow one from a mechanic friend? If you got a wiped out lobe, this will pick it up. It still might be a collapsed lifter, but you would get excessive valve train noise with that, like a clack clack sound.

Definitely do both the cam and lifters. Lifters are supposed to rotate in their bores, so make sure that the old ones all turn before you pull them out. The bores can be touched up with a hone.

Bob

I'm replacing the cam and lifters anyways. Just a waiting game now for Fedex to ship them. Anyone know how to check if the valves are leaking? Can i just use compressed air to see if it holds up the valves? Or is that not accurate enough of a test? Probably better to just remove the heads all together and check them that way while I've got everything else off, huh?

Perform a cylinder leak test. This procedure is more reliable than a compression test. The test equipment is more expensive, but its results are accurate. Borrow it.........
But of course, if you do love your car and have a litlle extra time, take the heads in and get now seals and get em checked.

Good Luck

Is your idle solenoid working or is the idle set with the throttle stop screw?[/QUOTE]


Yep, new carb and all. I had it and the timing adjusted about a year ago by a pro.
Stupid autozone, I'm never going there again. Those idiots said they placed the order for my cam and a week later I still had no cam. Turns out they never even placed the order. I went online to a place called Northern Auto Parts. Should have it Wednesday.
Well, have a great labor day people!!

OK, I've got the new cam and lifters in. Now the engine rotates but will not start. I am losing it people. I've got fuel pressure and everything is plugged in. I wonder if I put the cam in upside down, the timing marks on the cam and crank are supposed to touch each other right? With the no. 1 cylinder @ TDC? Or is the timing mark on the cam supposed to be pointing up as well as the crank timing mark? The distributor is in all the way, rotor pointing to the no. 1 spark plug wire. I'm pretty sure it lined up with the oil pump...although you can't see down there. You know, it doesn't sound like there's any compression while the engine is rotating. I don't know, I'm an intermediate home mechanic and don't really know the complete physics of this stuff.

Any help please??!!!

OK, I've got the new cam and lifters in. Now the engine rotates but will not start. I am losing it people. I've got fuel pressure and everything is plugged in. I wonder if I put the cam in upside down, the timing marks on the cam and crank are supposed to touch each other right? With the no. 1 cylinder @ TDC? Or is the timing mark on the cam supposed to be pointing up as well as the crank timing mark? The distributor is in all the way, rotor pointing to the no. 1 spark plug wire. I'm pretty sure it lined up with the oil pump...although you can't see down there. You know, it doesn't sound like there's any compression while the engine is rotating. I don't know, I'm an intermediate home mechanic and don't really know the complete physics of this stuff.

Any help please??!!!

The timing mark on the cam sprocket is supposed to line up with the timing mark on the crank sprocket. If you had both pointing straight up, that'd still work since one revolution of the crank will put them in alignment where they need to be.

My guess is that you got the distributor in 180 degrees from where it needs to go - the plugs are firing near TDC on the exhaust stroke. Try moving the plug wires to the opposite towers and see if that works, i.e. 1 goes onto 4, 5 onto 2 etc. Verify the firing order afterward, should be 1-6-5-4-3-2 with a clockwise layout on the cap.

In fact, I'm absolutely certain that's the case. Re-reading your post, you lined up the timing marks on the cam and crank sprockets properly (they don't exactly 'touch' in a physical sense, but I got what you meant), verified that 1 was on TDC ... what you SHOULD have done was pointed the rotor to #4 and NOT #1. It's a common mistake, I myself have done this more than once.

If the distributor is flush with the intake, then you're on the oil pump drive just fine - if the drive was not indexed with the distributor properly, the distributor flange would be about 1/4" off of the manifold.

I'm too lazy to type the thousand words, so instead ("A picture is worth a thousand words"):

http://72.19.213.157/files/TimingMarksAligned.jpg

Gotta love you guys. The distributor was about 90 degrees off but not only that, I had the rocker arms too tight in my attempt to adjust the valves. So I have to find another way to adjust them. Thanks, she purrs like a kitten now. I just hope she does as well on the road. Things are always different when you put it in gear and go.

Glad to see that you got it going again.

Let me ask you a question: Did you follow the directions for breaking in the cam?

When you got the engine started, did you run it to about 2000 RPM and keep it there for at least 15 minutes?

Not exactly. There were no intructions on that. My Haynes manual said nothing of breaking it in. I sure hope that didn't hurt anything...... Upon initial start up, I heard lots of clicking going on so I tightened the rocker arms up until it stopped. I'm really not sure how to adjust the valves, just going by the procedure outlined in the manual. I ran her this morning around the neighborhood and she runs horribly, maybe the timing is still off or the valves should be adjusted properly. The engine seems to be running very hot and continues to run well after the key is off. ( I don't mean good) This is not going very well. What's wierd is, when the engine is idleing in park, the idle is very high. When I put it in drive, the idle is so low it almost dies. This is with the timing right on the mark (according to my timing light), but don't get me started on the carb. I have no idea where to start on that.

You really have to have the motor together to do a valve leak test. Perform a regular compression test, see what the readings are. Then squirt about an ounce of mystery oil into the suspect cylinder(s) and repeat the test. This will rule out a really bad ring condition.

There are more sophisticated cylinder leakdown tests, but this should isolate a bad valve condition.

Bob

Sounds to me that the accelerator pump is bad in your carb... it may be that it just needs
to be tuned up as well (meaning idle, float, and mixture adjusted).

The run on that you're referring to is a condition known as "dieseling".

The carb is running on excess fuel after the engine is shut off because it's not adjusted
properly.

The falling flat on it's face is usually due to a bad accelerator pump in the carb, but as
I mentioned before, properly tuing the carb may cure the problem.

The way to break in a cam is to preoil the engine. This is done by using a drill through the
distributor hole to engage the oil pump. After that's done, then you stab the dizzy in and
start the engine up.

Once the engine is running, bring the RPMs up to about 2500 RPM and let it run like that for
about 20-30 mins.

You did use a liberal amount of assembly lube when you dropped in the cam & lifters... correct?

Remember to change your oil after the first 500 miles of driving to get the assembly lube out of
your crankcase... in fact, I'd change it at the first and second 500 miles, meaning once at 500
miles, then again at 1000 miles.

Scott

yeah i had a problem like yours with my 350 smallblock i used to have im my truck. it would run better with the affected cylinder's plug wire un-plugged. if you gave it more than about 2k rpm, it would just backfire up through the carb till you lessened up the gas. i believe it may have been burnt valves cause one of the heads had two white exhaust valves lol... the cam was probably pretty bad as well, i think im gonna pull it out and see if its messed up.

A friend of mine suggested an element in the distributor might be causing the problem. I can't think of what it's called, some kind of electrical harness or something that screws in. Sound like a possibility to anyone? Or maybe a vacuum leak? Would have to be a pretty big leak.

I still have no idea what to do. I have everything as it should be as far as timing and idle speed. When I put it in drive or everse, it "jumps" into gear and idles very low.

this sounds like a huge carb problem. i bet that motor would run great if you rebuilt the carb or paid someone to do it. i had a sudden problem on a 350 chevy and it suddenly wouldnt run at all and it was just the carb that needed to be rebuilt, which is in fact easier than its made out to be... especially on holley carbs. oh by the way, for the rocker arms, did you tighten them till they stopped clicking then let them back about a quarter turn or something like that?