tell me the story on my plugs...

[windsor306roush]

here is a sparkplug from my newly aquired 'stang that is running REALLY rich and smoking like a mofo(black/blueish smoke)
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this is different camera angles of the same plug(i forget what cyl it came from)

i replaced all of them w/ autolite ap25's...

 

[DMAN302]

Looks like blowby, old plugs, little lean in the last pic.

 

[windsor306roush]

here's the story: i'm trying to fix this really rich condition...the engine is running off of speed density...i think it has a cam(i dont know), and the idle is anywhere from 900-1100 rpm...i did a tuneup today(plugs, cap, rotor)...my last tank i got 80 miles to 3/4's of a tank(thats a'lil more then 6mpg!)...its really starting to piss me off...i traded this car for my '96 jetta that was about to blow its trans, and this car is my daily driver right now...any ideas?

thanks in advance

 

[DMAN302]

Pull the codes, can't diagnos problems without inside info. Poor gas mileage can be a result of many things, poor idle, poor gas milage, and the 'cam sound' is most often a result of a vacuum leak allowing unmetered air into the engine. Sd is very sensitive to vac leaks and car cause a host of problems . As stated pull the codes and find out what the car is saying...don't jump to conclusions and or throw money at assumptions.

 

[windsor306roush]

thanks for the info...i'll have to search on how to pull the codes...so far i have just replaced the cap/rotor(msd w/ alot of miles on it), and the plugs(and as you see they also had a lot of miles on them as well)...basically, i bought this car for 800$(bought wrecked jetta from brother for 300, and put 500 into it)

one more question before i pull the codes: what is the best way to find out if i have a vacuum leak? spray starter fluid and listen to the idle change? or should i go out and buy a vacuum gauge?

thanks again dman...

 

[DMAN302]

Well I followed every vac line..seems like a lot but really not too bad...to see if I could find any broken or disconnected lines. You could put tape on the ones you check so you don't end up going in circles as you follow through. Also carb cleaner is an good method to go with I guess...I have issues with spraying a flamable product around looking, but it seems to work and many have tried. You have some work ahead, but we've all been there.

 

[86bluecobra]

I like to use a tiger torch to find vacuum leaks. Just don't egnite flame let the propane find the leak for you. Turn torch on and run it over all vacuum lines and places where gaskets are to see if the idle jumps up if it does there is a vacuum leak there.

 

[windsor306roush]

good idea...i'm gonna do that tomorrow, after work...

 

[windsor306roush]

ok...i tried to pull the codes...didn't happen(last owner installed an aftermarket gauge panel and i think he f'd it up)...i also did a compression test, here are the results:
cyl 1: 160psi
2: 165
3: 160
4: 155
5: 150
6: 165
7: 165
8: 150

i traced the vaccuum lines today and fixed one major one i found...also, i set the base idle for 900rpm(instead of the 1500rpm it had)...
but it still smokes when i get on it...i'm thinking its due to the cam and speed density not compensating for it...

your thoughts?