[SOLVED] Fuel inside intake manifold from tuning ?

DEname

Greenie N00B Member
I recently got a fuel smell coming from my engine around the time i started getting maps and doing logs for tuning process, the car smells like fuel when i park it in the garage now. I took off the manifold thinking the injectors where leaking since i replaced the seals. The area around the seals look fine but the intake manifold is wet with fuel/oil in it is this normal ? It wasn't like that before when i took it apart to clean the valves , replace seals.

I changed the turbo cts4 cleaned valves, injectors cleaned and new seals then started tuning with PD before the fuel smell started
 
Explain your PVC system set-up. If you have a Oil Catch Can and how it is configured for your set-up. If stock be prepared to add these necessary parts. Higher than stock boost levels and high RPM with the improved rpm / turbo curve will require PVC system upgrades. Many threads here to help with your decision. Also a complete list of ALL mods done on your vehicle. State engine specifics too. Please search the forum for the types of information to help the audience give you great advice.
 
Got it
Stock PVC system and no oil catch can. The engine is stock

Mods
cts4 / 3.5 intake / 2nd cat delete / EBC / HPFP / CS top mount tuned on 91 by PD

thank you for the help
 
Despite the fuel smell, I doubt that’s gas in your IM. That’s most likely just oil and other blowby crap from the pcv valve, egr pipe and or the intake if the turbos shot and pushing oil. Perhaps the oil in the crankcase is so fuel diluted (happens) that’s why you smell gas. I know my dipstick always smelt like fuel after 3/4K. Smell yours. Stock block with high mileage plus big turbo equals a healthy amount of blow by/ fuel dilution. Obviously check fuel lines, rail, pump and connections for a leak.
 
That makes sense i will check that and get a catch can also. Would a damond motorsports pcv plate kit help with this at all ?
 
Yes. If you decide I would get the complete kit.
Now your question to yourself is how far you are going to go to correct this. Honestly I would-->
Change oil. Correct heat range plugs. Clean intake using solvent in a big container. A lot of fluid has to go into it and just trying to dump into cylinder runners isn't enough. Make sure PVC valve is new or if you go the damond kit make sure to get that option. Make sure value cover vent hose to air intake is clean and clear. Then run hard and see results.
--- Here's my opinion though ---
The reason why I'm asking this is, my first go round with 141k stock engine running great. Added a bnr S3 and needed modifications to support it. Within 500 miles, I was getting blow by and loss of compression and leak down numbers of 20-30%
You have a tired motor and you are trying to get 25% + HP out of it. So need to think of your commitment to continue and make a great running speed. Definitely worth it...I've done two complete rebuilds and never regretted my decisions. Painfully $$$ but should be expected too.
 
Any proper catch can set up will help and you can’t go wrong with any Damond motorsports product but you don’t need the full Monty fir your setup. Just his basic occ offering should be enough. You’ve got other areas to address and spend your money on first. I’d be considering colder plugs, egr delete, IM and TB tigs, coolant bypass, an intake valve cleaning a la walnuts and a FMIC to try and cool things down and possibly extend the life of this tired motor that’s being pushed hard. I’d switch to 5w40 as well and run 93 too and if after all this it’s still running good and holding together throw on a dp and retune for some additional gains. However I’d comp and or leak down test first before any of this. You gotta know what your working with. Good luck.
 
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No need to switch to 5w40 willy nilly that's old advice and relic of rubber rotella T6 ( don't run that shit there's way better oils for direct injection these days). Crank case pressure issues is what actually caused the issues on the stock turbo, there's threads on this and UOA on folks running 5w30 without issues

also fmic isn't always better than tmic, 540whp on tmic has been done and not redoing the ducting in bumper when swapping to fmic makes things worse as does not running an under tray. Swapping to 93 over 91 if not tuned for it really doesn't give benefit other than to the oil companies wallet. Also nothing wrong with a 91 tune especially if that's what's available.

Very much could be the PCV valve taking a shit with the oil in there. if you're swapping in a Damond occ if you have the extra funds putting on one for the PCV plates for the baffle it has is an added bonus.
 
Thanks guys. I just installed the CSt4 the car has 133 thousand miles on it and i don't drive it but once or twice a month i have had the car since 2016. I did most of the maintenance mods while i was in there, cleaned/blasted valves, new injector seals/sent out to get cleaned i did replace the pcv valve and did the coolant bypass. The only major thing i didn't do was the catch can as i was unsure if i really needed it. But seems like this is the problem. Ya also i see now that the top mount is a problem (i have a first gen) for heat as my bats temps went up so my tuner dropped the psi to 19 when finished, I have a 91 tune but i will do e mix tune as well, i might do a front mount as well to keep it cool and efficient.
 
Have you checked for leaks? Boost leak test if things are funky. We're hammering on pcv but rings could also be going unfortunately perhaps a compression test / leak down test, certainly if occ doesn't help
 
Have you checked for leaks? Boost leak test if things are funky. We're hammering on pcv but rings could also be going unfortunately perhaps a compression test / leak down test, certainly if occ doesn't help

No but my tuner never mentioned anything about leaks or anything funny happening. Good idea i will do a compression test but the engine seems strong but i should check it out
 
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