IDMR32 0 Posted March 6, 2022 Report Share Posted March 6, 2022 I was wondering if anybody has ever seen an issue like mine on my boosted R32. I have an HPA 7670 Turbo kit with a custom front mount intercooler setup. I have united motorsport 550 software on the stock filter/4 bar regulator returnless system. I have boost leak tested this engine up to 25psi and its solid. Compression test with an 8:1 spacer was 145psi across the board. Leak down test was done at 80psi and only leaked down 2 psi on each cylinder. My fuel trims are being crazy. While cruising they are between +10 and +25 and at WOT they are maxxed out at +25 and my air fuels are borderline at 12.8:1 in some cases…. Fuel pressure is great holding 56psi at wot. Not sure what my problem is considering no leaks. Ive swapped mafs and o2 sensors out and no change. VCDS says my ect sensors are reading correctly. I am chasing ghosts. If anybody has an idea of what could be wrong let me know. Thanks Link to post Share on other sites
RBPE 198 Posted March 22, 2022 Report Share Posted March 22, 2022 On 3/6/2022 at 2:20 AM, IDMR32 said: I was wondering if anybody has ever seen an issue like mine on my boosted R32. I have an HPA 7670 Turbo kit with a custom front mount intercooler setup. I have united motorsport 550 software on the stock filter/4 bar regulator returnless system. I have boost leak tested this engine up to 25psi and its solid. Compression test with an 8:1 spacer was 145psi across the board. Leak down test was done at 80psi and only leaked down 2 psi on each cylinder. My fuel trims are being crazy. While cruising they are between +10 and +25 and at WOT they are maxxed out at +25 and my air fuels are borderline at 12.8:1 in some cases…. Fuel pressure is great holding 56psi at wot. Not sure what my problem is considering no leaks. Ive swapped mafs and o2 sensors out and no change. VCDS says my ect sensors are reading correctly. I am chasing ghosts. If anybody has an idea of what could be wrong let me know. Thanks The maps not had a single o2 patch on it by the sound of it, much like HPA's ones, hence why the pre-cat bosses are in the exhaust mani. The ecu often gets confused by the readings and tries to compensate through learning, eventually leading to severe drift. FI maps on these can be quite different, if you're not using the turbo kit and fuelling/map that was developed with the kit then you need someone whose dealt with them before to retune it or modify it. I know Stealth have dealt with retuning these at times and ive done a few but no longer work in cars atm. So they're your best bet but its likely that, you can find some o2 patch info on the forum, how are your o2's placed etc.....plus one company's map can be very different to another's! Link to post Share on other sites
IDMR32 0 Posted March 22, 2022 Author Report Share Posted March 22, 2022 So its well known HPA’s software isnt the best, so I went with United’s “fix” software for the HPA kit, due to HPA’s driveability issues. I Was advised by Fred at United to plug HPA’s o2 sensor bungs in the manifold and run 1 single upstream sensor in the downpipe and 1 after the cat. Link to post Share on other sites
RBPE 198 Posted March 28, 2022 Report Share Posted March 28, 2022 (edited) On 3/22/2022 at 5:05 PM, IDMR32 said: So its well known HPA’s software isnt the best, so I went with United’s “fix” software for the HPA kit, due to HPA’s driveability issues. I Was advised by Fred at United to plug HPA’s o2 sensor bungs in the manifold and run 1 single upstream sensor in the downpipe and 1 after the cat. Ah okay....I'm not sure what this "fix" patch is like but it sounds like it has the single o2 patch. However, the hpa stuff tends to be very much air based and so would need quite a few mods or just a complete remap really! Anything like different inlet manifolds/with or without the change over function, maf sizing, even the injector flows are scaled to the relative air mass and as such, I'd assume every remap would need to take these all into account really. You ideally need to talk to UM and find out if the "fix" corresponds to your parts etc. Anything like a miss-matched sized maf/hfm will obviously throw the fuelling out! It may just need a remap to tweak the fuel given the changes in map structure but it's likely all related to that if you've eliminated all the hardware/leak side of things. Also check the return/returnless side with them as most go mk4 and zero the map out - like I say, only UM can tell you what they've done. Edited March 28, 2022 by RBPE Link to post Share on other sites
IDMR32 0 Posted March 28, 2022 Author Report Share Posted March 28, 2022 Well looks like Im at another dead end. United’s tune is for my exact setup. I bought the parts they recommended (CTS intake manifold, CTS 4” MAF housing, and Bosch 550cc Injectors). They insisted its not their tune and must be a hardware issue. I think Ive narrowed it down to the MAF sensor. I ordered a new one. We will see. Link to post Share on other sites
IDMR32 0 Posted May 10, 2022 Author Report Share Posted May 10, 2022 So, I installed a new map sensor and my fuel trim numbers improved greatly. I also found a spot on my CTS intake manifold that is porous and leaks around 25psi. Also, my fuel pressure started dropping and it turns out all my fuel line clamps loosened up on my in-tank walbro 450 fuel pump. Tightened everything up and the car has been running decent. Im buying new submersible fuel hose for the in-tank pump and pinch clamps to keep it all tight. Im going to throw some epoxy on my intake manifold until next winter where I can fix it the right way. Getting closer to a good running 3.2 vrt. Thanks for your input! Link to post Share on other sites
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