Hi,
I'm new to this forum. I have an 87 El Camino SS with a 305, it has Thorley Tri Y headers, custom exhaust with flowmasters,edelbrock performer intake, edelbrock cam(mild RV cam), am going to be putting on a H.O. air intake(as soon as it arrives), all else is stock. My problem is when I remove the air intake lid it has a strong smell of gas, I do not think this is right, but I could be wrong. Also, my milage is not good around 9-12mpg, it seems to run fine, of course it does not feel like it is making enough HP with the above combination. Idle seems good, is a little ruff in the morning but not to bad. What do you think might be causing this? Any help would be great! Thanks


August

 

Sorry for the double post, my fingers were working to fast.

August

 

Remember one thing first: it's almost never the carb's fault.

Now, bad fuel mileage can be from a bad O2 sensor feeding the ECM false info on the engine's A/F ratio (replace it if you don't know how old it is or over 50K miles). Also, the choke may not be getting fully open (that'll wreck fuel mileage for sure). Visually verify that the choke plate above the primary bores is getting fully open on a warmed-up engine. Is the ignition timing set correctly? Stock spec is 6* BTDC for your engine with the ECM's timing wire disconnected. Any vacuum leaks? These engines had MILES of vacuum hose and lots of valves and diaphragms that could go bad, sticking open, closed, or just leaking vacuum.

Beyond that you'll need to hook up a scan tool to see things like the ECM is seeing them. A bad TPS sensor (throttle position), bad VAC sensor (manifold vacuum) or a knock sensor that thinks it's hearing knock when it really isn't can all contribute to poor mileage.

Only crack into the carb as a last resort. If you're not familiar with digging around inside these carbs you're at least 50% likely to make it run worse than it did before.

 

Damon,
My scan tool shows everything is working fine, I don't think I have any vacum leaks, I've been replacing vac lines in hopes that was the problem but so far no luck. I'll check the o2 sensor and replace, I think it's only a couple of years old but not 100% sure. On the Vacum line issue, I don't hear any "whistling" going on, what would be another way of checking? Thanks for the help.


August

 

Spray some carb cleaner around on likely leak points (gaskets. hoses, any connection point. If you hit a leak the idle will speed up and smooth out. Also, on hoses that disappear into unknown places pinch them with some pliers (not the hard plastic ones- they'll crack). The idle will slow down and smooth out if one of them is leaking somewhere (then you gotta go track the leak down).

 

Beyond that you'll need to hook up a scan tool to see things like the ECM is seeing them. Does any one know a scan tool that does that?:lala: :lala:

 

Hi guys,
I rehooked up my scan tool this morning, and now it shows that I have a error code number 41, any info on a fix for this would be great. Thanks


August

 

YES
A computerized scan tool (or a laptop with the right software) that reads serial data from the CCC.