Power loss | Forum

Just went for a 3 mile drive and bus ran fine. Typical.

How is your spark?  Are the spark plugs black?

Snoop I will look at the plugs when I get a chance, just got back from a weekend in Baltimore. I just drove the bus (and yes it has been raining here) and after about a mile it lost power again, really bogging down to the point where I had to pull over to let other cars pass. Even in neutral when I revved it I could hear it sputtering a bit. I kept going and after a few minutes it started running properly again. Went to Home depot, shut it off, came back out it ran fine. No problems the rest of the trip home. 

When this occurs, and Im trying to give it some gas and accelerate, I can feel the occasional blip where for just a second it lurches forward with power, but it never lasts long enough to really get going, if that makes sense. It does feel similar to when I had AFM issues, so I will be cleaning the insides of that as well. Will update as I get into this.

Plugs are a perfect tan.

Could your gas tank be clogged or vent line blocked?

I had the tank out maybe two years ago and it was very clean inside. I just checked the fuel pressure and its a steady 33 lbs or so, and I had written the install date on the fuel filter, so I know it has low miles on it. I started it tonight and it seemed like it wanted to stall on decel if I tapped the throttle, so I raised the idle (at plenum) and enriched the fuel mixture (at AFM) a half turn each. Drove the bus and it ran great. However, it had been warmed up a bit by then so I still don't know if the issue has been resolved. Unfortunately I don't live the kind of life where I can let the motor go cold and re-test repeatedly. At idle the motor purrs like usual. I'm planning on camping in NY state this weekend, a 3 1/2-4 hour drive, so I'd like to get this sorted. Will update when I know more. I haven't messed with the AFM yet.

Well went up to the Catskills and back to camp at Mongaup Pond and had no problems. Even drove to town (ok, the brewery) on Saturday and had no problems. At this point I am cautiously optimitic!

Awesome!

Well I took my bus out last Sunday and it acted up again, after sitting for a few days and after more rain.  I pulled over,shut it off and looked in the engine bay. I now suspect the wire running from a spade connector on my positive battery terminal to the fuel pump. I jiggled it then the bus ran fine. I am going to secure that connector (solder!) and Ill report back.

About a week and a half ago I inadvertently broke a fuel nipple off of the bottom of fuel tank (don't ask) and had to replace the tank. Luckily a good friend had a spare and I was only sidelined for a few days, and got to camp the following weekend. I was under the bus to swap my positive battery cable, which I believe was original to the bus. In the process I installed all new fuel lines, fuel filter, and of course the battery cable including connection mentioned in last post.. I haven't had the power loss issue since and I think I may have solved the gas smell I used to get whenever I filled the tank. Will post updates in a few weeks to see if this is all just wishful thinking.

Is the issue resolved?

I was sure it was resolved because it stopped doing it from the time of last post, (oct 2018) but this week it started acting up again. Same thing; It starts fine, idles, goes great out of the driveway and up the road, but after I drive for a mile or two it starts slowing down and losing power. No backfiring or missing, I put it in neutral and it revs fine, but under load I can't get the rpms up to shift into the next gear. I pull over and poke around in the engine bay, not really finding anything, just jiggling connections and checking hoses then it runs fine. I just went through and checked around in the engine bay and found the hose to the charcoal canister disconnected and the bottom of the "S" tube wasn't fully on the plenum, and I corrected those issues and will test drive in a few minutes to see if there is any change. I will say this; my battery is getting old, but I checked and it holds 12.44v and doesn't really drop much when the ignition and headlights are switched on, so it seems fine. This is driving me a little bit nuts!

Performed like a champ on test drive. Will take it out early tomorrow before I feel convinced it is ok.

So far, so good. Am keeping fingers crossed!

Great!  see you at HCBF?

Problem persists! It seemed to go away but it is back with a vengeance. Checked/set tappet clearances a few days ago, then went through some tests on it today; fuel pressure good, compression OK, Temp sensor #1 tests good, but temp sensor 2 shows low resistance cold, so will be ordering tomorrow and should have by the end of the week and will update. Right now if I drive the bus, as before it runs great for about one minute then power drops off sharply, to the point where I have to pull off the road and I can't even get the motor to rev out of gear. Up until now this has only happened after wet weather and/or when the bus has sat for a week or two. Now it occurs every time I take it on the road. A few minutes of cursing and stressing and it eventually works itself out, but performance is still a bit off, (as far as I can tell with and underpowered over worked and well worn motor).

 not trying to hijack but Let us know how it works out, my 65 is doing something similar.  I can drive for a while but as soon as I stop, she dies even if I try to rev it as it is slowing down.  It takes 15 minutes or so before it will start.  After about the 4th time, the starter quits even trying to turn over.  I can roll start her.

Ugh what a PITA this has been, I keep thinking I have it beat then it reappears. Put in new temp 2 sensor,and while I was in there I changed the lead from the coil to the dizz because I suspected it wasn't making a good connection. (I made up my own ignition cables) Drove it to Lowe's and back and it seemed better, definitely more oomph and the power loss didn't show itself. Of course it's too early to tell but I felt a change for the better. Then on the way home my pass side rear blinker stopped blinking. Again, so got home and cleaned up connections, chased wiring etc. and that seems fixed but that's another one that returns after I think I have it fixed. Snoop I have forgotten all I ever knew about the type I issues, but is your motor getting really hot when you drive it? Kind of sounds like overheating to me. Next time it happens try touching the dipstick; if it's too hot to keep your finger on, you may have a valve adjustment or timing issue.  (Just speculating of course). I will post after I drive mine a bit more.

OK, I drove the bus Saturday morning to the store and the power loss showed itself, so it ain't the temp sensor or ignition coil lead. Drove up to a campout about 45 minutes from home (ran ok) and once I got there I swapped out my AFM with a spare I had. It rained overnight so I figured conditions were ideal for this issue to occur. Bus drove great the whole way home, felt better and once home I parked it for 4 hours or so then took it for a ride to the store. No issue. I'm going to drive the bus a few times this week, in as many varying conditions as possible to see if I might actually have found the trouble. Now researching AFM repair/adjustment. Fingers crossed!