Sometimes it does sometimes it doesn't

[Tims450SL]

My 78 450 SL sometimes runs like it was new. sometimes it feels starved. I have NOT yet replaced plugs, wires, cap/rotor cap. fuel pump, fuel filter. I just got done doing that on my 75, and I am like here I go again. My 75 runs 100% better with all the new goodies, but I and others have noticed a real gas smell while the car is running from the exhaust...a friend followed me home the other day and commented on it. The 75 runs pretty badly, and I am ashamed. I also have a fuel waste that is almost un believeable in it. What could it be? It runs alittle funny cold then heats up and is like presentable to drive, but not what it should be. I know this was a 2 parter question but I am ready to commit suicide. Anyone know what to do or try? I know it needs to go to a specialist. But I am determnined to try to understand it and try to fix it myself. I know that is ego...but I have never had this with these 450's before. Usually it was a wire or plugs or fuel filter, etc. Thanks for the help! I mean it!

[ScottinSoCal]

Originally Posted by Tims450SL

My 78 450 SL sometimes runs like it was new. sometimes it feels starved. I have NOT yet replaced plugs, wires, cap/rotor cap. fuel pump, fuel filter. I just got done doing that on my 75, and I am like here I go again. My 75 runs 100% better with all the new goodies, but I and others have noticed a real gas smell while the car is running from the exhaust...a friend followed me home the other day and commented on it. The 75 runs pretty badly, and I am ashamed. I also have a fuel waste that is almost un believeable in it. What could it be? It runs alittle funny cold then heats up and is like presentable to drive, but not what it should be. I know this was a 2 parter question but I am ready to commit suicide. Anyone know what to do or try? I know it needs to go to a specialist. But I am determnined to try to understand it and try to fix it myself. I know that is ego...but I have never had this with these 450's before. Usually it was a wire or plugs or fuel filter, etc. Thanks for the help! I mean it!

Are you asking about your 75 or your 78?

[timm9]

I also noticed a fuel/gas smell from my 82 last fall before placing it in storage for the winter. The smell seemed to be at the rear only. I had assumed it was a small leak in or around the filters or accumulator. I intended to "tear into it" this spring but the snow is not completely gone yet.

Tim

[jb2008]

Assuming that your 450 is fuel injected , check for black smoke from exhaust (have someone follow you) you may have to jump on it . If they/you see black smoke have the fuel press. regulator and/or oxygen sensor checked . 450's also had timing chain issues .

[Tims450SL]

my 1978 it runs alittle better-I put a new cap and rotor cap on...wires this weekend with plugs (non resisitor bosch) and I have a feeling my furl filter may be a huge culprit. It runs strong now but has this weird like miss sucking fuel miss i think...thanks scottsocal