My parents just recently purchased a 93 motorhome with a 460. It has pretty much sat the last four years. There are a few problems they are experiencing. First off, when the motor is cold sometimes you can turn the key all you can hear is a click but will not crank. It can take up to 10 or so off-on cycles to get it to crank. When warm it will do it from time to time but usually will go on the second or third time. Sometimes it is also delayed, if you keep it turned for a second or two then it will fire. I'm hoping this may be a loose or dirty connection as I have not checked into this at all.

The other problem when it is cold is it will crank and crank with no fire. I can cycle the key several times and hear the fuel pump kick on and off with no help in the starting. I can crank it for 30 seconds with no fire. It will kind of act like it wants to but no luck. After a lot of cranking I can barely tap the gas and it will fire up great. It runs a little rough for a second but then smoothes out. After the initial fire it will start right up everytime to problem.

The last problem occurs when it is warmed up. After being driven and then left to idle for a few minutes it acts as though it is loading up. You can give it gas and it will start to spit and sputter. If you give it even more gas you loose even more power and it sounds as if it is backfireing but not sure if it's through the exhaust or intake. Saturday is the last time it did this and I noticed when it was idleing the check engine light was on for a few seconds until I tried to floor it. It will barely pull its self down a level roadway. If there is any kind of incline it will not move. Feels like it's running on 4 cyclinders. I can put it in neutral and rev it up or shut it off and restart with no help. But if I get it going down the road and wind it out in first then it's fine??

Yesterday decided to do a little tune up and changed the air filter, fuel filter, and plugs. The starting problem is still there but has not repeated the warm motor sputtering yet, though I think it will again.

Any help would be appreciated, Thanks

 

if it sat for 4 years, the fuel system is probably very gummed up from sitting.

i suspect it is fuel injected being a 93, so my guess is that the injectors will need a good cleaning to get them working properly.

you can try running some fuel cleaner through it, but that doesn't always work 100% at cleaning the injectors. take it in for a professional cleaning.

rgds
Mike

 

Yes, it's fuel injected. I've put seafoam in the gas. I'm wondering if it could be the pcm, egr, or something along those lines. I'm going to try and get the computer scanned to see why the light came on the other day.