****FIXED**** (Bad TPS) Renegade 800 Sputtering

[Mike_Metzger]

So I picked up this Renegade for $4500. Seemed to run awesome. Got it home and was doing some laps with my son when I noticed it was losing power and sputtering at 2,000 rpm's. Almost like its hitting the rev limiter (I know its not, but for sake of diagnosing that's what it sounds like)  Stopped driving, came back after it had been sitting for awhile, and it ran awesome again. Issue pops up after driving for 5mins or so and engine is up to temp. Machine has 1,100 miles on it

Looks like the old owner may have been chasing this issue as well. 

-New spark plugs
-New thermostat
-New Fuel Pump
-New Fuel Filter
-Temp sensor.... Not sure what else... 

Any advice for chasing this down........? 

 

 

[Real]

Check fuel pressure as mine did similar at high fuel pressure. No more than 48 psi . Also if you have the tube from valve cover to air inlet remove that and put it in a jug to see if blow by is an issue 

[Mike_Metzger]

16 hours ago, Real said:

Check fuel pressure as mine did similar at high fuel pressure. No more than 48 psi . Also if you have the tube from valve cover to air inlet remove that and put it in a jug to see if blow by is an issue 

Ah interesting, I just bumped the pressure up (too high) and it seemed to run a little better, as far as it had more power, but still sputtering in the same RPM. Also, I noticed this time that it isn't just once it's warmed up, even cold its doing the same thing. Almost like its pinging off the rev limiter... 

Also, here is a shot of the plugs, obviously not running rich..... ??? 

[Real Leroux]

What is the air filter like 

 

[Real Leroux]

Lower the pressure to 40 psi and run with out the air filter and retest . Sounds like Air fuel ratio issue 

[Mike_Metzger]

17 hours ago, Real said:

Just lowered the pressure to 40, seemed to run a little better, but really low on power. When the fuel pressure is high, seems to have more power but falls on its face fast, when fuel pressure is low, it seems to operate more normal(climbs higher in the RPMs before sputtering), but really low on power. 

[Mike_Metzger]

Maybe an electrical issue? Coil packs are weak?? Bad sensor…. Clogged injectors 🤷‍♂️

[Real Leroux]

bring it up to 50 and try also clean that intake . 

[Mike_Metzger]

Same result, runs well enough to putt around, but definitely not running like it should. Maybe I’ll try and get vid of the sputter 

[Mike_Metzger]

Here’s some photos of e engine

 

[Mike_Metzger]

I believe I may have found the issue, pulled the injectors, and while the outlets looked okay, clearly there is debris clogging up the inlet side. This HAS to be what’s going on. Going to clean them up and I’ll report back 👍

[Mike_Metzger]

Unfortunately that didn’t fix it. Same problem persists. Perhaps electrical/voltage issue? I have 3 new coils showing up tomorrow…. 
here’s a shot of my homemade injector cleaner. 
 

[Dan B]

Did the new coil packs fix the issue?  Check the plug gaps (.035"-.043", 0.9mm - 1.1mm).  They look a little wide (but the look may just because of the close up shot of the plugs).   Also check for a vacuum leak that may be causing a lean mixture.  Fuel pressure on those engines are spec at 50 psi.

[Mike_Metzger]

1 hour ago, Dan B said:

Did the new coil packs fix the issue?  Check the plug gaps (.035"-.043", 0.9mm - 1.1mm).  They look a little wide (but the look may just because of the close up shot of the plugs).   Also check for a vacuum leak that may be causing a lean mixture.  Fuel pressure on those engines are spec at 50 psi.

Getting the coil packs today, fingers crossed. The plugs were at .050 I changed them to .035 and no difference 😣 Any advice on where to start looking for vac leaks?

[Dan B]

I think your coil packs it a good possibility based upon my experience with my SUV.  Try that first.  Vacuum is generated and starts at the intake manifold.  Anything and everything that has a tube coming from the intake manifold and downstream at any T-fittings, actuators should be checked.  When vacuum lines get old, they get brittle and they can get small cracks that can be hard to see.  Don't overlook the seals on the fuel injectors.  From my information, the fuel injectors inject fuel into the intake manifold at each cylinder; not directly into the combustion chamber (like a diesel engine does).  If this doesn't work, I'd be at a loss.

[Mike_Metzger]

1 hour ago, Dan B said:

I think your coil packs it a good possibility based upon my experience with my SUV.  Try that first.  Vacuum is generated and starts at the intake manifold.  Anything and everything that has a tube coming from the intake manifold and downstream at any T-fittings, actuators should be checked.  When vacuum lines get old, they get brittle and they can get small cracks that can be hard to see.  Don't overlook the seals on the fuel injectors.  From my information, the fuel injectors inject fuel into the intake manifold at each cylinder; not directly into the combustion chamber (like a diesel engine does).  If this doesn't work, I'd be at a loss.

Just put the new coil packs in, didn’t fix it 😢 I’m going to thoroughly look for vac leaks and maybe get a new mass air flow sensor…..  

[Mike_Metzger]

Here is a link to a video of the issue that I posted on the Joyner Facebook page. 
 

Video link

[Mike_Metzger]

Unplugged the Throttle Position Sensor and HOLY SHIT this thing flies!!!!!!! 
SOOOOOO STOKED!!!