[rlc]

While here in Yuma we've taken a couple of great rides with the last one being through the Barry M. Goldwater Range.  This ride ended up being close to a 100 mile ride.  Anyway, for the first 3/4's of the ride our Z8 Trail ran flawlessly including two stretches of about 10 miles of washboard road.  After visiting "The Wall", at the Mexico/U.S. border we headed back.  At the first washboard road people were holding back from the one in front, so they could hit the bumps a bit faster in order to smooth out the ride.  When it was my turn I started out with the intent of riding them at about 30 mph, or so.  About three minutes into it my SXS lost power and dropped speed to about 15 mph.  At a certain gas peddle position It would speed up to around 20, but had absolutely no power.  Thinking the air filter might be dirty I pulled over, let the engine idle while I knocked some dirt off of the fairly clean filter.  While I was doing that another person was inspecting around and had opened the gas cap and noted no suction.  I took off again and in about 3-4 miles it happened again.  I let it idle, opened the cap again, no suction, and it ran into Yuma fine.  Yesterday, thinking the tank vent check valve might not be working I checked there and this 2019 Z8 doesn't have one.  I did notice that the air intake pipe had worked it's way off of the filter box, so I reattached that.  Finding nothing obviously wrong I reassembled, fueled up, and took it for a hard eight mile sandlot ride.  It ran great.  SO, here are the facts.   I was very low on gas after that long ride.  No gas tank check valve to break.  Air intake pipe had come off the box.  No suction on the gas tank when cap is removed.  Day was about 75 degrees.  Temperature gauge ran at 3 bars all day long.  No lights flashing except gas gauge bar because of low fuel.  Has anyone else experienced any problem like this?  Any ideas, suggestions, etc?  Thanks

[NMKawierider]

Let me toss in that the tank vent check valve is built into the tank. The vent line plugs right into it. And that its main function is to not allow vacuum on the tank but will allow pressure....and with that amount of riding I would have expected at least some pressure...although it's actually only an ounce or so. My tank vent check got stuck open and although made no difference on how it ran, it did shoot gas up the tube and into the frame where they have it stuck into. I installed a secondary check inline to fix that because I refuse to buy a new tank to fix that check. Not sure about the loss of power....might be several things but it looks to be fuel supply related. Might check pressure and volume....power to the pump....connections....and the filter itself may have water in it.

[rlc]

NMK - Thanks for the feedback.  I found no sign of gas being forces back up the vent line after removing the cover.  Interesting that there is a check valve in the tank, but no part number or note to identify that hose connection (check valve) into the tank as a valve.  I'm going to take it out into the desert again to today just to see if I can recreate the loss of power.  If not and all seems well it's off to the KOFA Mine area with hopes of another good ride.  Someday, I'm going to learn how to post picks from my Android phone.  Thanks again.

[rj2wenlrn]

RLC - Curious to see what you found...I ran into the same issue.  Drive from Chandler to Mesa and the 800 did the same thing 3 times.  All pavement so it wasn't rough.  I would like to find out the issue as well.

[rlc]

We've been on three rides since my power loss problem and our Z8 has performed flawlessly.  All I can guess the problem was is that it was low on gas and the pump was just picking it up when I stopped and what gas was there stopped sloshing so the fuel line would re-fill.  Heading into Mexico today for a few hours and tomorrow were going back to the KOFA Wildlife Refuge for one last trip before heading back to the Rockies for the summer.  Great rains over the last few weeks and the desert is starting to show it's colors.  Should be a beautiful ride.

[rj2wenlrn]

Thanks for the response.  Great to hear it ran well.  Mine my have been a gas issue as well as it was sitting for 3 months but I haven't had it out since.  Please let me know if you ever find out anything different. Have fun!

[rlc]

Okay, today it did it again.  Engine lost power, same area that it lost it in last time.  Thing is, we've driven a few hundred miles since the last time this happened with absolutely no problems.  So, today, lots of wash boarding at 25-40 mph.  Ran well for 15 miles then no power.  Decided to limp back into Yuma @ 5-15 mph then after about 5 miles, nothing..wouldn't pull itself and the EFI light came on solid, no blinking.  A jeep came along and offered to tow us back into town, but the guy in the second Jeep wanted me to try something first.  He had me turn the ignition on, but don't start.  Listened for fuel pump to turn off then turn off ignition and do it again.  So I turned on, listened, turned off, five times.  He told us to get in and to go ahead and start it up.  And, if it starts go like hell toward Yuma.  Well, it worked and EFI light went off.  It worked for about 5 miles then started losing power again.  Pulled over, cycled fuel pump, off we go again where we made it back to the house...No EFI light on.  So, while talking to this Jeep Guy he said that sometimes EFI's or fuel pumps will get hot and stop working, but when you prime the way he had me do, sometimes there is enough syphon created to make it run.  What I didn't get from him is, is it the fuel pump or the fuel injection that could be bad?  Also, why would the Z8 run for a few hundred miles with no problem, then all of the sudden, this again?  Thanks for any thoughts.  It will go to the dealer in about a week when I get back to Montana.

[NMKawierider]

Okay, today it did it again.  Engine lost power, same area that it lost it in last time.  Thing is, we've driven a few hundred miles since the last time this happened with absolutely no problems.  So, today, lots of wash boarding at 25-40 mph.  Ran well for 15 miles then no power.  Decided to limp back into Yuma @ 5-15 mph then after about 5 miles, nothing..wouldn't pull itself and the EFI light came on solid, no blinking.  A jeep came along and offered to tow us back into town, but the guy in the second Jeep wanted me to try something first.  He had me turn the ignition on, but don't start.  Listened for fuel pump to turn off then turn off ignition and do it again.  So I turned on, listened, turned off, five times.  He told us to get in and to go ahead and start it up.  And, if it starts go like hell toward Yuma.  Well, it worked and EFI light went off.  It worked for about 5 miles then started losing power again.  Pulled over, cycled fuel pump, off we go again where we made it back to the house...No EFI light on.  So, while talking to this Jeep Guy he said that sometimes EFI's or fuel pumps will get hot and stop working, but when you prime the way he had me do, sometimes there is enough syphon created to make it run.  What I didn't get from him is, is it the fuel pump or the fuel injection that could be bad?  Also, why would the Z8 run for a few hundred miles with no problem, then all of the sudden, this again?  Thanks for any thoughts.  It will go to the dealer in about a week when I get back to Montana.

All that is telling me it has a fuel delivery problem. Could be pump...could be trash or water in the tank getting to the intake screen,...could be water in the fuel filter. It also could be a stuck-shut vent check valve. Nothing serious or tough to fix.

[rlc]

Thanks NMK.

[rlc]

Once I got back to Montana I took my Z8 to the shop where I bought it to have a few things looked into.  First, was this loss of power issue.  The mechanic noted, "Injector light comes on", "scanned for codes, P0500 VSS No signal"  Their remedy for this and what they think is also the reason behind the loss of power that I experienced was to clean connector and install new speed sensor.   Along with this problem I had foggy headlights and a bit of moisture inside them.  Because these are not sealed headlight housings no warranty exists for this, so we just left them.  The only other major thing, and one that has been bothering me from the time I bought it, is a squeal/loud noisy in engine compartment.  Mechanic notes: "Repaired exhaust leaks, loosened/adjusted header pipes and muffler was misaligned."  I can tell you this made a huge difference in overall noise.  SO, there you have it.