phils89sc
Registered User
I posted a message here recently about alot of blackish grey smoke dumping from my 89 SC's exhaust under heavy acceleration. Well, I didn't get any responses, so I will try it again. I am pretty sure it is either bad catalytic convertors or my supercharger is finally dying on me. At any rate, my problem happens at higher RPM's in usually 2nd gear and 3rd (by the time I hit high RPM's under full throttle in 4th gear, I am usually push about 135 mph, hehe!!). What happens is I get alot of black smoke coming from the exhaust, and whenI look at the boost gauge (however innacurate the factory gauge is...), it reads almost 15 psi (way too high). Now, I have to say that I have stock everything, except for a 70mm MAF, and removed air intake silencer. When I get to this higher RPM and the smoke starts pouring out, the supercharger whines very loudly and the power drops off kinda like she is straining or pulling something. I shift into third and the power comes on good till about 4k rpm's and them drops off like in second, again, very high boost levels (could be spark know too I guess, even though I am ALWAYS running 93 octane). Another symptom I have is that when on the highway, my gas mileage is sort of crappy (about 21-22 mpg tops). My first SC (also an 89) got almost 30 mpg (28-29) on long highway trips using cruise control, so this seems strange. I just changed the plugs and wires to Borg Warner wires and Autolite double platinum plugs set to .054" gap a week or so ago, but this was pre-existing before that. I was thinking either my cats are partially clogged or my supercharger is failing (seems that the whining and the power drop off/smoke happen at the same time).
Also, I ran a code check on the ECC a few days ago, all 11's clear across the board, no codes period, KOEO, KOER, or stored codes at all were picked up. She idles very well too , but exhaust smells sort of sweet, but not like rotten eggs or anything. I was thinking about punching out the cats, but they seem sort of difficult to get in to.
I would appreciate any advice/help you can offer.
Thanks
Philip Stocker
Also, I ran a code check on the ECC a few days ago, all 11's clear across the board, no codes period, KOEO, KOER, or stored codes at all were picked up. She idles very well too , but exhaust smells sort of sweet, but not like rotten eggs or anything. I was thinking about punching out the cats, but they seem sort of difficult to get in to.
I would appreciate any advice/help you can offer.
Thanks
Philip Stocker