I've got a 12ht swapped 2h HJ75 Troopy and it's been running like a champ for the past year with no hiccups. Yesterday when driving, it began to idle low and rough at stoplights. When I'd take off, it'd sputter until about 1800 RPM, blowing a haze of white smoke. Then once I'd hit 2000 rpm, it'd clean up, stop smoking and be fine. As soon as I'd slow down at a stoplight though, the idle would dip and it'd be rough again. All of 1st and the first half of 2nd would be rough but 3-5th was like normal.
I drove home, replaced the fuel and air filter, checked the Bosch replacement primer, didn't see any noticeable leaks. I also checked the idle speed per the FSM and did the typical troubleshooting it recommended.
Some notes/questions:
-Turbo boost is fine and turbo is operating as it should.
-Last year I installed a Webasto pre-heater to heat up the coolant to make cold starts easier (we live at 7,000').
-The PO ran the return diesel line from the injection pump back to the main supply line right below the injection pump just outside of the hard fuel line above the chassis rail, so I installed the diesel drip line for the heater into the return. All these clamps are super secure and there are no leaks. It's never given me an issue and I've been running it all winter long.
-Should I run the return back to the tank or at least the filler neck overflow?
-I filled up the tank yesterday at the gas station two blocks from the house. It was really cold out so I didn't want to cut the engine off after starting it up immediately so I left it running while I filled up. I doubt this has anything to do with it but it's worth noting.
I'm stumped here and hoping it's not the injection pump or injectors. It's been running fine up until this point and the injectors nor the pump show any leaking fuel.
Thoughts?
I drove home, replaced the fuel and air filter, checked the Bosch replacement primer, didn't see any noticeable leaks. I also checked the idle speed per the FSM and did the typical troubleshooting it recommended.
Some notes/questions:
-Turbo boost is fine and turbo is operating as it should.
-Last year I installed a Webasto pre-heater to heat up the coolant to make cold starts easier (we live at 7,000').
-The PO ran the return diesel line from the injection pump back to the main supply line right below the injection pump just outside of the hard fuel line above the chassis rail, so I installed the diesel drip line for the heater into the return. All these clamps are super secure and there are no leaks. It's never given me an issue and I've been running it all winter long.
-Should I run the return back to the tank or at least the filler neck overflow?
-I filled up the tank yesterday at the gas station two blocks from the house. It was really cold out so I didn't want to cut the engine off after starting it up immediately so I left it running while I filled up. I doubt this has anything to do with it but it's worth noting.
I'm stumped here and hoping it's not the injection pump or injectors. It's been running fine up until this point and the injectors nor the pump show any leaking fuel.
Thoughts?
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