EV (hot start) "Issues"

[LowRyter]

I've been having Guzzi issues lately.  The Greenie is still in the shop AWP for fuel pump (blows the 10A fuse).  My EV has displayed some TPS symptoms and has been having some hot start issues..... some advice regarding the strange EV problems would be appreciated.

1st:

It has a schizophrenic idle.  It either idles normally (1100 rpms), or on it's own, it will idle fast (2000 rpm).   Now here's the other thing, when it idles fast, it run real good.  When its idling normally, between 3-4k rpms, it surges at steagy throttle and backfires when I down shift (I attributed this to my TPS).  I am guessing it's running too lean when it's in a mode to idle normally.  I have no idea why it wants to idle fast.

2nd problem:

It won't restart when I fill it at a gas station.  This has happened a couple or three times now.  I believe the fuel pump is energized (can't hear that well), cranks hard but won't fire.  Opening the gas cap, doesn't help.  Then I take off the side cover to look at the fuses and it fires up.  I am thinking about getting relays from Pyro Dan but I am just shooting in the dark.

This is all voodoo to me.

[LowRyter]

I am not going to put paxil in the tank. 

[fotoguzzi]

when is the last time the valves were adjusted? they could be too tight.

have you messed with the idle trim dial on the CPU? now there is where some voodoo is..  it's not always the TPS at fault but could be.

could you have an air leak when it idles schizo? (at the throttlebodies/intake)

2nd problem could also be tight valves? or a relay for sure.. get some new ones from PyroDan. ignition switch also comes to mind, wiggle the key next time it won't start.
Realys are cheap, TPS not so..would be best to get a diagnostic picture before just replacing it.

[rodekyll]

I'm thinking a loose or broken head temp sensor rt cyl, up near the head.  They're famous for breaking their mount.

[LowRyter]

temp sensor?  OK.  I'll take look.

I can adjust the valves but I'd be surprised if they are a problem.  If anything, they might be a little loose-they clatter a little to my ear but not by much. 

I haven't played with the idle trim since I came back from the Salida National Rally in 2009.

[fotoguzzi]

I'm thinking a loose or broken head temp sensor rt cyl, up near the head.  They're famous for breaking their mount.

not on a '98.. in the left rocker cover.. the worst possible way to take engine temp..

[krglorioso]

I put Pyro Dan's "GEI" relays in both Stones.  I believe the cost was $18 for 10 relays, a few years ago.  Cheap insurance.

Ralph

[Mackers]

I put Pyro Dan's "GEI" relays in both Stones.

Ditto.  Transformed my Stone.

[LowRyter]

I could've pulled on that sensor wire taking the valve cover off.  And I get some relays. 

But still......

[Jerryd]

I put Pyro Dan's "GEI" relays in both Stones.  I believe the cost was $18 for 10 relays, a few years ago.  Cheap insurance.

Ralph

Pyro Dan??

[fotoguzzi]

Pyro Dan??

http://dpguzzi.com/

[Dean Rose]

I put Pyro Dan's "GEI" relays in both Stones.  I believe the cost was $18 for 10 relays, a few years ago.  Cheap insurance.

Ralph

Order 2 sets, install one and have the other for spares.

Dean

[delrod]

John, carefully unplug the temp sensor-clean with some type aerosol cleaner and reinstall or just as likely you may discover the broken temp sensor holder causing your problem. Your symptoms sound identical to what I had early on when my EV was rescued from the chicken house that had been it's previous home. (I do not recall the erratic idling being nearly as definite as you describe) . If the temp sensor holder doesn't break it is a quick and dirty process.

[LowRyter]

thanks Doug and Merry Christmas

[LowRyter]

here's an update.  I installed pyro Dan's relays.  I did find that the cover on the Temp Sensor was ripped, so I cleaned the sensor, wrapped the cover with electrical tape and re-installed it.  Took my test ride.

Bike still coughs in the 3-4k rpm range, I do believe it's the TPS.

Hot start did hesitate but it did start AFTER I grabbed some throttle.  I am thinking the hot start issue might be fuel delivery.

[Kiwi_Roy]

A couple of things to check.
The fuel filters have been known to clog with rust on an EV. Disconnect the fuel return hose where it connects at the front of the tank. Direct it into a bottle and turn on the key, you should get a full pipe flow coming back, if it's just a dribble the filter is blocked and the fuel pressure at injectors will be much higher than normal. The filter doesn't block off on first starting, I think if the bike is shut down for a while sufficient rust falls away to let it flow normally for a while.
Another sign of a blocked filter is a very noisy pump.


If you think it's the TPS why not tap into the signal strap your multimeter to the tank and monitor it.
It's easy if you have the old P8 ECU remove the back off the plug and connect a wire to pin 17, the other lead goes to chassis

[LowRyter]

great info. Might as well change out the fuel filter. 

I'll give the TPS check a try.  Thanks.

[pehayes]

A couple of things to check.
The fuel filters have been known to clog with rust on an EV.

The issue isn't so much with the huge filter under the tank tunnel, but rather with the dinky fittings and filter up inside the electric petcock.  Remember, on a fuel injected machine, the fuel is flowing constantly like the circulation in a fish aquarium.  Carb bikes only had to gravity drain the fuel that was consumed.  Any flecks of debris in the tank get migrated quickly to the petcock area.  The fuel pump starts straining and gets noisy.  Easy enough to drain and rinse the tank and clean the petcock components.

Patrick Hayes
Fremont CA

[Kiwi_Roy]

Patrick,
          You also pointed out that the moat drain plugs causing the tank to rust in the first place.

It was certainly the case with my EV.

Rust mort took care of that.

Roy

[Bill Havins]

John,

Pull the TPS and see if there is fuel in it.  If so, check this thread:  http://wildguzzi.com/forum/index.php?topic=73658.0

If there is no fuel in the TPS, reinstall it, set it to 375 milliVolts at idle position, and then follow Roy's suggestion.  But here is an addition to that.  You can get a quick read of how the TPS is functioning without starting the bike.  As Roy said, connect your DVM to Pin 17 and ground/earth.  Then with the key on, but the bike not running, watch the voltage as you slowly turn the throttle to WOT and back to idle.  Do this several times.  If you see anything other than a "smooth" linear response to turning the throttle you may have TPS issues.  If the TPS checks fine, look for your solution elsewhere.  You'll save $325 or so by doing the above unless the TPS is shot.  If it is, I have an extra I can loan you to see if it will solve the problem.

Bill

[pehayes]

You'll save $325 or so by doing the above unless the TPS is shot.  

Isn't the cheaper Harley Davidson alternative TPS still available?  IIRC, that TPS was only about $60 and seems to work just fine.

http://www.guzzipower.com/TPSRep-Yaniv_A.html

Patrick Hayes
Fremont CA

[Bill Havins]

Isn't the cheaper Harley Davidson alternative TPS still available?  IIRC, that TPS was only about $60 and seems to work just fine.

http://www.guzzipower.com/TPSRep-Yaniv_A.html

Patrick Hayes
Fremont CA

I was recently quote >$100 for the Harley part (different resistance pattern and a special order) and $325 +/- for the Guzzi part.  Made me break out in a cold sweat...

[LowRyter]

Isn't the cheaper Harley Davidson alternative TPS still available?  IIRC, that TPS was only about $60 and seems to work just fine.

http://www.guzzipower.com/TPSRep-Yaniv_A.html

Patrick Hayes
Fremont CA

Been there done that (perhaps they sent me a bad one).  (There is a whole thread on this and the ducati replacement)

BTW- the one that's on my bike that I've tried to replace is a Harley TPS too.  

[LowRyter]

changed out the fuel filter and cleaned out the screen.  The screen was clean but there was definitely resistance when I blew through the filter.

Didn't have any hot start issues.  So I am crossing my fingers.

The suspected TPS backfire and spit is still there.  So another problem for another day.

Thanks guys for all your help.   :bike

70 today and got some riding in.

[LowRyter]

Damn.  Hot start problem again.  Took about 5 minutes and a dozen tries for it fire.  Dunno.  Never happens at home when I can pull a plug to check ignition.

 ::(

Need to check TPS and Temp Sensor.  But it's a shot in the dark.  Too intermittent to trace. 

[geoff in almonte]

Sounds like a coil problem.  I had one go bad on a Harley I owned.  Symptoms were as you describe.

When the coil was hot, the spark would go away and no amount of kicking and cursing would start the bike.
But if you waited 20 minutes or so - all was good until the coil heated up again.  We checked everything that could possibly affect the ignition system and it wasn't until we bench tested the coil for several minutes that the problem was revealed.

If you've already investigated this, I'll just shut up and go away.

Good Hunting!

G

[Kiwi_Roy]

Sounds like a coil problem.  I had one go bad on a Harley I owned.  Symptoms were as you describe.
 

Don't rule out the plug leads, my EV had the crappy resistor lead as well as resistor caps, new copper leads made the world of difference. On inspection I could see inside the old carbon ones where it had been arcing.
If you pull the plug caps I think from the cap to chassis should read about 8000 Ohms, both similar.

[LowRyter]

actually I just talked to a local Duc mechanic (I was trying to see if he could find a TPS) and he suggested that it might be a cracked coil.  (The coil is an unknown quantity as it was exchanged during an early ignition trouble shooting party at the Salida Rally in '09.  That problem was cured due faulty connection on one of the igniter boxes) 

But doesn't the EV have two coils?  If so, that wouldn't be the cause of both cylinder not firing.

He made great suggestion:   Carry a spare spark plug with me.  If it won't start, pull the plug wire and insert the spare plug for a quick ignition test.

If the ignition proves to be good, then he proposes installing a fuel pressure gauge.

Both seemed logical ideas.  I'm packing a spare plug with me.

Anyway, he didn't have a TPS and the bike started right off and I left.

[Wayne Orwig]

Sorry if this is repeated, I don't see it.
If this is a 98, and you have the external fuel pump. That means, that when it is hot, it is easy for the pump to vapor lock if there is ANY obstruction in the suction line. Make sure the fuel solenoid is opening, if it has one. And make sure the fuel strainer in the tank is clean. Also, the fuel line suction line from the tank should have a braided steel cover over it to keep the heat from bothering it.

[LowRyter]

Wayne, I just changed the fuel filter and took the screen out (see above).  The filter did seem to have some obstruction.  I thought it was fixed until today.  The bike does have the electric petcock.  So that is also a point of concern.  it could also be the fuel pump.  Next time it happens I plan to check the ignition with a spare sparkplug.  If that checks out, I'll go with the fuel pressure gauge.