Airstream w/ 454 Power & idle problems


tmarrs

New Member
I have what I hope is not a serious problem. I just bought a 1995 Airstream Land Yacht 33 ft with a Chevy 454 engine.
During the test drive the temp gage went right to the red zone and pegged right after being started. After a 10 min drive we used a handheld laser temp gage and read the temp as 205 deg at the thermostat and 185 on the radiator. Engine did not seem hot, so we assumed a faulty gage. The 10 minute test drive did great & I purchased the unit "as-is".

The unit cranked right up to drive home, however I noticed much reduced power when attempting to accelerate. About 2 miles later, it started to run rough, and my top speed became 35 mph. I had to hold brake & a little gas to keep it from dying at intersections, and it would knock & backfire if I attempted to give it too much gas to slowly make it back up to 35mph.

The unit had been on a consignment lot for the last year, however they stated it did get driven around the lot every few weeks. There is fresh gas in the tank, and the generator runs strong and smooth.

I'm sorry for the long post, but I am at a loss for explaining why a test drive would go so well, and the trip home 30 minutes after signing the paperwork seemed like a different engine. I limped it back to the dealer & left it in the lot since I couldn't get it home.

HELP !
 

TexasClodhopper

Senior Member
Re: Airstream w/ 454 Power & idle problems

"During the test drive the temp gage went right to the red zone and pegged right after being started."

Perhaps your test drive did not go as well as you were wishing. Sometimes troubleshooting a problem means NOT ignoring symptoms.
 

C Nash

Senior Member
Re: Airstream w/ 454 Power & idle problems

Sounds like a problem in the distrubator. Check the coil pickup and module. Distributer will have to be removed to replace the pick up. Could also be the rotor and cap. check them for carbon tracking.
 

JimE

Senior Member
Re: Airstream w/ 454 Power & idle problems

I purchased a 1993 Winnebago Brave with a 454 and the first thing I found was that the terminals in the distributor cap were chewed to nubs, replacing it and the plug wires made a world of difference. Another thing to check is the Catalytic Converter. If it is old and clogged, it will die going up hills, be non responsive during acceleration. etc. I'm not a mechanic, but have run into similar situations and this is what I found to be wrong.
 

Kirk

Senior Member
Re: Airstream w/ 454 Power & idle problems

tmarrs
It almost sounds like timing to me. You don't say how many miles it has but I would think that the timing chain could be a factor. I too am a non-mechanic but have had an RV with that engine. Let us all know when you learn something, if you will.
 

tmarrs

New Member
Re: Airstream w/ 454 Power & idle problems

Thanks for all the great imput! I have traded this engine problem for another one and need help again !

I returned to the lot and did a very good engine inspection while it was cold. I found that one spark plug wire had popped off the plug. I put it back on and wow - back to the way the test drive was!

I drove it home, staying between 55-65 mph. A friend following me said it put out a small puff of black smoke about 5-6 times during the 30 minute ride home. The engine ran OK - a little rough but didn't seem like anything a complete tuneup would not take care of.

I got it home and parked it in the driveway for 2 days. Last night I started it up to move it and... now have a loud engine knock. I removed the engine compartment cover and it seems like it is coming from the left valve cover. It is very loud, like someone is hitting the inside with a hammer. I never heard any knocks (and I listened for them) before this. NOW WHAT ! Does it ever end?!?

Troy
 

tmarrs

New Member
Re: Airstream w/ 454 Power & idle problems

I forgot to mention - it has about 58k miles, & when I heard the knock I immeditally turned it off. I restarted it once more after taking the cover off, and I only ran it for about 5-6 seconds that time - I don't want to make anything worst than it already is.
 

C Nash

Senior Member
Re: Airstream w/ 454 Power & idle problems

Might be a loose valve. Which cover did you have off dog house or valve cover? Could also be a piece of carbon on top of the piston. Get a piece of broom handle and probe around the engine while listening on the end of the stick and you should be able to hear the knock. these engines were notorious on plug wires so invest in a quality set.
 

ARCHER

Senior Member
Re: Airstream w/ 454 Power & idle problems

Hey Chelse, do they sell them broom handles that ya can hear through down in yur neck of the woods? Just teasing a little. My ole Chieftain (89) with about 16k miles on her is still working petty good. I bought new plugs and plug wires last fall and was gonna put them in before I headed to Texas for the winter, but after I looked at the effort, I decided to wait until I got home and do it this summer before Florida trip. Still trying to get up the guts to tackle this job on my own. I don't breathe so good in tight spaces, so hoping the auto fairy will stop and take care of it. I'd ask Momma to try and do the job, but I might get booted out of the house. I'll get to it. Even with only low, low miles on the ole 454, I thought it a good idea since I doubt if it has ever been done and she is getting a little old like the rest of us. Sorry about the rambling..... ;)
 

rlmurraysr59

New Member
Re: Airstream w/ 454 Power & idle problems

I agree with the plug wire situation, been there done that with my last big truck. And if you had one off then there was probably some sludge build up in that cylinder. I would also check the EGR valve cause they carbon up too. Might check the fuel filter to make sure it didn't varnish a little while it was in storage. The 454 is a very good engine but prone to blow sparkplug wires and have engine "ticks" when it first starts up. I have a new 496 (8100) on a Workhorse chassis and once in a while I will dump a quart of Marvel Mystery Oil in the gas tank to lube the valves while driving. Been told it is Wonderful Stuff. :)
 

rlmurraysr59

New Member
Re: Airstream w/ 454 Power & idle problems

Oh, forgot one thing I wanted to mention. About your heating problem. Make sure the serpintine belt is in good condition and the fan clutch is working properly. My big truck gave me a problem one time and it turned out the fan clutch wasn't working and the electric fans weren't kicking in either. Relay had to be replaced. :)
 

C Nash

Senior Member
Re: Airstream w/ 454 Power & idle problems

Archer, Snapon would come by while I was listening to that broom stick and try to sell me a fancy looking tool to listen but I just told him that would make me look like a doctor and then I would have to charge more :eek: . Shoot Archer we can put thos wires on in Wally World parking lot. Well, could have at one time:dead: :dead:. Was trying to help gson work on his car today and had to get him to help me up:dead: :dead:
rlmurray better watch that telling of mystery oil We might guess your age :laugh: it does work in the older vehicles We also had good luck curing the lifter leak down on the 454 by using straight 30 weight oil.
 

rlmurraysr59

New Member
Re: Airstream w/ 454 Power & idle problems

Yea, I thought it had disappeared from the shelf. But it is still available. I was told that what makes it a Mystery is where it comes from. It is the pure oil that is squeezed out of crude when making gasoline. Doesn't have any contaminants in it. Don't know if the story was true, a man older than me told me that.
 

tmarrs

New Member
Re: Airstream w/ 454 Power & idle problems

My nextdoor neighbor mechanic listened to the knock and said it was the lifter. We did a complete tuneup - the rotor and plugs were terrible. All replaced, along with new wires. I also changed the oil and switched to mobile one and a quart of Lucas oil stablizer. It runs awesome now - quiet, and is so smooth it barly shakes or vibrates at all.

Great news, until the same neighbor gave me the bad news. Texas Clodhopper had it right - the overheating indicator should not have been discounted as a faulty indicator. Although the mechanics promised me it was faulty - my neighbor put alot of water directly in the radiator, and now the thing works - showes the engine run about 190deg. This means that it was driven home from the dealer while it was actually overheating!

Although the engine sounds wonderful and smooth to me, my mechanic says he hears something that makes him think I may need a valve job. We will do a compression test tomorrow to find out how bad it is. He said if it has a problem, it most likely happened while it was overheating.

I am just kicking myself for believing the mechanics at the dealership and ignoring the "faulty" indicator.
 

rlmurraysr59

New Member
Re: Airstream w/ 454 Power & idle problems

Hope the compression test comes out alright. Asked your mechanic if doing the valve job might cause it to start burning a little oil. Sometimes grinding or replacing the valves and increasing the compression will cause an older engine to push more oil past the rings on the pistons and create an oil burning problem. Make sure he checks the cylinders and pistons while he has the heads off. No use pulling the heads twice if there is a ring job in the future.

Personally, I would run it a while and see if the valves and guides reseat. If you had poured anti-freeze or cold water in the radiator while the engine was hot you would have blown it for sure. But since you let it cool down first it might just be okay. When an engine overheats the oil thins and trys to act as a coolant too. Sort of scorches the oil like grease in a frying pan. Also, don't use straight water in your engine. Make sure you fill it with the recommended anti-freeze. If it calls for the pink stuff don't put ethaline-glycol in it. (the green stuff)

It has always amazed me that dealerships hire young mechanics, who have a large input into their reputation, and refuse to pay them a decent wage. They train them, show them the equipment they need to do the job, and when they get a little experience they move on to an outside repair shop that may pay slightly more money. Auto dealers are notorious for doing it too.


Good Luck
 

tmarrs

New Member
Re: Airstream w/ 454 Power & idle problems

OK.

We completed the tune up, changed the plugs, wires, rotor & cap, fuel filter, PCV, and all the belts and hoses. When you run the engine with the air filter off, there is a loud sucking noise. We have checked and can't find any vacuum leaks at all.

The engine runs like crap and backfires. It runs worst than it did when I drove it home before the tune up! I limped it to the gas station 2 blocks away to fuel it up, and I could only go about 8-10 MPH. It sputtered and backfired the entire way.

This is the same thing it did to me when I tried to drive it home in the very beginning - found that problem to be a plug wire off... I checked and double checked the plugs, wires, and even double checked the firing order. Everything was fine.

Now I am full circle back to the start - Why did it drive 65mph on test drive, 10mph and like crap when I tried to take it home, 65+ the next day after finding the problem, and now after a good tuneup back to 8-10 mph?????

All ideas and stories of your past engines are welcome. I don't mind sinking another thousand or so into it to get it running great - I just want to know what is wrong, and throw money at the right problem and not fix anything that ain't broke!

TG Marrs
 

C Nash

Senior Member
Re: Airstream w/ 454 Power & idle problems

The backfire tells me the problem is electrical and still would check into the module, coil and coil pick up. Worn cam or lifters, valve spring would cause a backfire but it would not go and come. If it has a vacuum advance on the distributar remove the vac hose and see how it runs. Sometimes the wires on the pickup will break and the vac advance movement will cause it to lose connection. The sucking noise with the air cleaner off is normal. Drive it down the road and floor it with the air cleaner off and I will hear it here in Alabama :laugh: Check fuel pressure and volum of flow. Have you changed the fuel filter?
 

tmarrs

New Member
Re: Airstream w/ 454 Power & idle problems

Yes - fuel filter was changed with everything else.

Here is something else interesting... There are 2 injectors - idle the engine and put your hand under the right side injector blocking the fuel and the engine dies. I can do the same thing on the left injector and the engine will keep running without too much difference. The fuel coming from each injector appears to be equal.
 

C Nash

Senior Member
Re: Airstream w/ 454 Power & idle problems

Has the ck engine light came on? Is it working? Do you see it with just the key in the on position?
 

tmarrs

New Member
Re: Airstream w/ 454 Power & idle problems

The light comes will come one shortly after the 1st backfire. If I just idle and don't give it any gas it will not come on.
 
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