V-Strom scholars wanted: '04 DL1000 won't run under 5000 rpm

[dontpanic]

I recently stole purchased for a very reasonable price a 2004 DL1000 knowing it didn't run right.

Three months later I've exhausted all my knowledge and haven't gotten it running properly.

I decided to start a new thread rather than muddy-up RandyO's V-Strom build thread.

Symptoms:

• Starts.
• Idles.
• For the first 90 seconds of running time, it'll accept low throttle openings.
• From then on, it won't accept throttle at all under 5,000 rpm. It will sputter and die.
• The one time I was brave enough to take it out on a highway it was beyond frightening. It would only stay running over 5,000 rpm. (Try pulling into your driveway like that!)

What I've done so far:
Scoured the Stromtrooper forum and VStrom.info for ideas
Downloaded the shop manual and wiring diagram
Put it in dealer mode and checked for codes - none
Checked the air filter - it's fairly new and in excellent condition.
Adjusted the idle speed
Installed a new throttle position sensor (and adjusted it properly)
Installed a new battery
Uninstalled a set of relays put in by a prior owner for electrical accessories
Ultrasonic cleaning of the injectors
Confirmed that the tank is properly vented
Confirmed that the throttle bodies are tight to the air filter housing and to the intake boots
Sprayed carb cleaner on all the linkages - everything moves freely
Tested the fuel pump (slightly below specs)
Disassembled fuel pump & ultrasonically cleaned (a bit of gunk, not much; output improved after cleaning to a bit better than specs)
Trim plug wires (following post #2 below) (could easily reach rear; did not do front)
Sought out corroded ECU contacts (post #12)

Things still to do:
Check throttle-body sync
Upper throttle-position sensor (following post #5)
Seek out corroded electrical contacts elsewhere.

I'm obviously missing something, but I'm now stumped as to what it might be. I could continue throwing parts at it (like a new ECU) but that's going to get very pricey very quickly.

So, NESR brainiacs: Where do I go from here?



Edit: I'll put a similar post on Stromtrooper.com in a day or two.

[golden chicken]

Is it running on both cylinders? Could have plug wires arcing out our not seated properly. Common advice on SVRider is to cut a little bit off the end of the plug wires and reattach the end for a fresh, clean connection.

Also check the fuel pressure and volume, though my instinct is more ignition related of an issue than fuel.

[dontpanic]

When it runs (like at idle) it seems to be running on both cylinders. But something definitely changes shortly after that.

I assume you're speaking about trimming the plug wire at the coil side, correct? I've never done such, but I can't recall a plug wire that would allow trimming at the plug end. I'll check it out next weekend - I think you may be on to something.

[Kurlon]

Trim it at the plug side, that bike uses normal coils, the plug ends will unthread from the wire.

[RandyO]

1st gen V-stroms ( don't know about the newer ones) have pretty primitive Throttle Position Sensors, the carbon surface gets all buggered up for the lower throttle openings required for under 5k rpm

I know mine sputtered from bad TPS between 2500 - 4500 , did you replace both TPS ? or just the primary ? if not, do both

another issue I had was because I keep it in my barn, or basement, where the ambient temp is around 60°, but I roll it out before I start it, if the ambient temp outdoors is 30°, I have to babysit the throttle till it really warms up, cause immediatly after starting , it senses the 60° coolant temp vs the intake temp, and thinks its' already warmed up, if it is left outdoors in cold, it starts normally without babysitting the throttle

[dontpanic]

Thanks, @Kurlon. I didn't know that.

@RandyO, I only did the lower TPS. If trimming the plug wire doesn't remedy the issue, I'll do the upper one. Any trickery to it? Any adjustments needed like the lower one?

Also, I'm a cold-weather wuss now, so the bike only gets ridden when the outdoor temp is 45 or higher (usually much higher). It lives in an unheated garage, BTW.

I *have* wondered if the coolant temp was involved in the issue, though, based on the emergence of the issue after about 90 seconds of running.

[PurplePackage]

check the valves

[nick5446]

That's a weird one...

I wouldn't think the fuel pump has anything to do with it. Check for vacuum leaks? Also surprised there are no codes, as that was going to be my first suggestion.

Was this a known issue when you bought it? Did the PO do any diagnosis?

[tls25rs]

No idea if Suzuki remedied their issues with wiring prior to the '04 year or not but on the early year TL1000 variants there were a lot of problems with the grounding of electrical components causing all sorts of driveability issues. The way the wiring harnesses were constructed would lead to joints where multiple ground wires come together in the harness corroding and therefore not providing a good ground. All else fails double check all the cabling on the bike and verify that this is not your issue.

[PurplePackage]

No idea if Suzuki remedied their issues with wiring prior to the '04 year or not but on the early year TL1000 variants there were a lot of problems with the grounding of electrical components causing all sorts of driveability issues. The way the wiring harnesses were constructed would lead to joints where multiple ground wires come together in the harness corroding and therefore not providing a good ground. All else fails double check all the cabling on the bike and verify that this is not your issue.

these were fixed by 98 iirc.

http://micapeak.com/TL1000S/faq/p3.html#Q24
http://tlmods.com/FAQ.aspx#runs-like-shit

[dontpanic]

@nick5446, yes, the previous owner disclosed the issue but did not do any diagnosing.

I'll post up again when I've tried Kurlon's and RandyO's ideas.

[RandyO]

All my work is done at dealership, when I had to replace the TPSs, was one of the easier diagnostic, and before I started serious winter riding, after a couple winters, my wire harness got cancer, but probably the toughest diagnostic, was random cutting out and coming back, turned out to be one corroded contact on my ECU, very delicate to clean, but they did

[dontpanic]

Update:

Tried more things and have updated the original post.
Spoke to my longtime mechanic buddy who encouraged me to seek out bad grounds.
Discovered that a home-made version of an Ivan's timing retard eliminator had been spliced in. Removed same. Runs much better!!!
Will take for a short ride today.

[dontpanic]

Took for a short ride. Alas, no change.

Starts and idles fine, runs on both cylinders right to redline when stationary.
Once underway it acts as if there's no spark under a variety of conditions: throttle/no throttle; above 3,000 rpm under light & load heavy load; but under 3,000 it's fine under a very light load but won't accept throttle input.

Back to the drawing board.

[golden chicken]

IAP sensor hooked up properly?

[dontpanic]

It ought to be. I'm kind of a nut about making sure that any connectors I futz with get reconnected properly.

[butcher bergs]

Are you absolutely certain the o-rings in the fuel pump housing are in good working order?

Also, is all the wiring related to the fuel pump housing in known good condition?

What's the possibility of a pinched fuel line?

[RandyO]

Discovered that a home-made version of an Ivan's timing retard eliminator had been spliced in. Removed same. Runs much better!!!
.

I can pdf you a color wiring diagram if you want, I have it plotted out poster size taped to a big white board so I can design my axillary wiring and interconnection

[RandyO]

ack ! have I previously mentioned it.. clogged fuel filter, I did the bypass, and drilled a hole thru the stock in tank filter, and added an inline filter (high pressure for FI, I chose one I can get at NAPA)

[PurplePackage]

check the valves

,,