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Running rich

747 views 7 replies 3 participants last post by  Room2three7 
#1 ·
I put uv dye in fuel system before going to a Dyno to make sure I wouldn't leak on the shop floor (trying to be considerate). I spotted no leaking and all appeared well. Tune went pretty good and eliminated some minor mistakes after a few pulls. Once I left the Dyno I went home, parked the car and did a walk around. decided to check the oil and noticed a smell of gas. I remembered the dye and pulled out the black light only to notice my dipstick was glowing radioactive green! My tuner said I just needed to change the oil. So I did.... Four times and it's still the same watery viscosity, same cartoon green color. I drove 60-70 miles after each change hoping it would clear up. Got a 89 gt heads, cam, intake, headers. Street setup all around and only 700 miles on the engine. Could it b the code 15 causing the rich condition? Tuner also took out my o2 sensors. Said he programmed the chip w/o it. Also called auto pro (the 1s who make the dye) to see if it was normal for dye to slip pass the rings. They said unlikely. I'm going to add the dye to my other car and check that oil soon just to see if the same thing plays out but thought I'd see what anyone else thinks
 
#2 ·
my advise, read you plugs and see what they look like. if they are black, you are indeed rich. if you were running rich enough to put a lot of gas in the oil, you would be running like absolute crap. if nothing else, get an aem 02 gauge. im a carb guy and run them on everything i have. easy to see your afr's and not burn your motor down.
 
#3 ·
So go wideband for the o2? I can do that. I checked the plugs but it's all so new it's hard to tell a change. They do smell like gas tho. I also did a compression test on all cylinders and they all hold between 150-170. That's why I don't understand why my fuel is mixing so much. Pulled codes but deleted o2 sensors during tune. Could I put them back on despite the tune? I mean my oil was radioactive green. And thanks for the info. I'll look into a wideband and see what's going on. But would 1 cylinder with a lot of fuel show a noticeable increase or subtle? Jus hope it's not a valve hanging a bit or injectors going south.
 
#4 ·
when I bought my 88 gt it had so much gas in the oil when i changed it . I tossed it on the camp fire it was like jet fuel. changed out the mismatched injectors and greased the rubber seals when I installed the new ones , seems to have fixed it. yeah you don't wana wash the the rings down with fuel on your new motor. are you puffing blue out the exhaust. i would of kept the o2 sensors. how does the new tune no when to adjust fuel trim?
 
#5 ·
i don't know how it knows when to trim but I've heard it runs off the factory loop because the ecu doesn't notice any o2 sensors. This is why I think the chip has its own loop or something programmed in it but it still doesn't know what to do for afr outside of what it's told to do via the chip. Scares me and has me worried about this new motor. Definitely going to pull injectors out too. They're the only things I haven't checked and I've switched 2 fprs. And the exhaust isn't puffing at op temp, just some blue especially after letting it sit for a few days on a cold start. Clears up after 5-6 mins. I swear i think it's the code 15. No keep alive memory from the chip. I want to clear codes but am stuck wondering if I should plug in the o2s till I get the wideband like op said
 
#6 ·
probably won't not be your fuel pump reg. thiers ways of telling if they gone bad. unless it was an aftermarket one set way to high. you have 27 pound injectors which seem big for your setup. imop. 24's might be a better choice. you could have a stuck injector/s. Incorrect timing , timing chain stretch yet unlikely if brand new. i had the same issue. but I have speed density and had bad ecm n cracked vacuum hoses n mismatched injectors. previous owner was a dunce. my cars is stock besides the headers and flowies so it can happen to a stock stang not just a tune . There are a lot more guys with exp than myself out on that subject (tuning). plus read this it will explain the diff besides a normal o2 sensor/stock vs a wideband one.

Wideband O2 Sensors explained | Haltech - Engine Management Systems. 14-1 is the right air to fuel mix for a combustion engine . goin up up or down is a rich or lean condition.
 
#8 ·
Good stuff guys. Time to get busy I guess. As always thanks for the 2 cents
 
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