powdahbonz
Recruit
- Joined
- Sep 1, 2010
- Messages
- 2
[FONT=Verdana,geneva,lucida,"lucida grande",arial,helvetica,sans-serif]Yesterday[/FONT]
Took mechanic out for run to identify issues. 03 Z175TXRB hpdi-711 hours..idle to about 1200rpm sounds normal..above 1800-2000 and up, starts to bog, chug, stutter. Can get above 2500 in reverse with no chugging or issue. That part is odd and leads me to think TPS worn on the block and not allowing all cylinders to engage. Symptoms are same on main tank and portable tank. Same before and after decarbon of o2 sensor. Symptoms same before and after plug replacement. After launch in May 2019, had symptoms that led me to inspect VST-small oring from pump body had degraded-June 2019, replaced VST filter and gasket(do this annually), cleaned thoroughly but did not take apart pressure regulator- replaced vst tank pump in 2018, replaced low pressure pumps June 2019(one diaphragm was leaking slightly), replaced upstream filter canister June 2019..was good from July 2019-September 19 and started hesitating again in September before taking out. So here’s where I’m at..ran YDS software yesterday, when getting to 2000-2500 rpm, fuel pressure(high) would surge from 705psi down to 475, up to 690 back down to 565, spike up to 705..you get the gist. Vst pressure has been starting at 35psi building to 47psi.
Thinking that the issue is upstream in Injector’s, mystery filters and high pressure pump. No error codes on YDS. All readings were in normal range. The only flash of red was the high pressure reading when over 2000rpm.
Reached out to injector Rx in Houston, shared video, said that based on summary and video sent along, recommended sending injectors, fuel rail and hi pressure pump in. The reverse not causing the same symptoms makes me think its electrical related to TPS or neutral switch. Looking for guidance before doing the full monty and taking apart hi pressure pump, injectors, and fuel rail. Going to test resistance on TPS Thursday and try adjust the forward tab and make sure there is connectivity.