Sailormon

I’m not sure what the black stuff was Pop Bob.. it looked more like a carbon buildup on the sensor tip. When I took delivery it had some gas in the tank but since then I’ve run only non ethanol from a designated 5 gal gas container. At the end of the break in along with the recommended maintenance I also changed the in line fuel filter and the air filter too. The last oil change I replaced both again so I don’t think air or fuel could have been contaminated but who knows? I’ve got some cables coming so I can hook a laptop up to the ECU for future issues. Does anyone know how the motor connects to the shaft on the throttle valve inside the throttle body? There are 2 screws holding it to the body on the exterior but I’m just curious how it disconnects if those screws are removed. i doubt any of the black stuff came through there but I’m just curious how it hooks up. I’m glad you got it working again John! Scott

Hey John I ended up going back over everything I had already tested (fuel pressure, injector, spark, spark plug, etc). I pulled the coil and that end of the plug wire had corrosion. Although my spark tester showed a spark it certainly wasn’t delivering as it should. It took a week to get the plug wire and I thought I had it for sure. Nope same problem. Cranks great but no start. If I gave it throttle it ran fine but reduced toward idle it quit. I went back to the throttle body (I had previously taken the induction hose off and checked the air cleaner and sprayed out the throttle body) and this time concentrated on the Idle Air Controller. I pulled the sensor and the end of it was black with junk. Cleaned that up then also pulled the MAF sensor (which I had replaced already) and sprayed those out as well. Where the sensor fits there is an opening that goes into the throttle body and when I sprayed that all sorts of black stuff came out. I put everything back and tried to start a couple times. On the 3rd try it started right up, ran snotty for a few seconds, probably due to all the throttle body cleaner, then cleared up and idled perfect. No problems since I hope you got yours working John if not you may want to check the plug wire at the coil. It may be beneficial to pull that IAC sensor and take a look at that too. Let me know what you find as it looks like only a question of time before something else happens to mine! Best, Scott

I have almost the same issue as John. Parked my 2022 Coleman 400, (seatbelts crossed and hooked up continuously) then it refused to start until pressing the gas pedal. Stalls when I let up on the gas. Checked connections on seat belts( where is the seat belt limiter?), removed all connectors and sprayed with electrical cleaner. Changed MAF sensor, checked fuel flow (new fuel filter), good spark checked with inline tester (new spark plug). As I understand it, the MAF is also a temp sensor that determines if it’s a cold or hot start and schedules fuel accordingly? About a month ago on first start of the day it cranked but no start. Pulled MAF connector , sprayed and it started right up. When it happened again 2 days ago I ordered a new sensor to help eliminate possibilities after cleaning didn’t work. Does the ECM fail on these at times? Ive had to replace the water temp fan relay and I’m just wondering if the sensors and electrical control are the primary fail points of the 400? If someone with experience on this rascal could elaborate it would be greatly appreciated! John I apologize, not trying to hijack your thread it just sounds like a similar problem. Scott