Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: Haystack on June 05, 2005, 12:49:24 PM

Title: black exhaust.
Post by: Haystack on June 05, 2005, 12:49:24 PM
I just recently go my car running again, (you may remember all of the no start threads I started, SorryBut I still have the problems with gas milage. My exhaust is JET BLACK and full of gas. When I stop somewhere or park, I leave a long black mark all the way from where I slowed down to when I stop. It leaves layers of soot. My timining is slightly off, But I have had this problem before it started doing that and the timing I cant get fixed until pay day. I am sure that this has nothing to do with my timing(okay maybe alittle but not all) Basically, What should I switch out. I found lots of vacume lines off, but put them back on and it didnt change anything exept idle. My TPS sensor is off, It idels around 600 to 800 rpm. But I am sure that the spark plugs are on right, and that the timing is as close as I am going to get it. I have spent hours working on both. I dont think that it is slack on the timing chain, Because I did a couple of tests, (minus looking at it and replaceing it). Right now I think that this is some kind of sensor. I got a EGR and a EGO code when I pulled codes. Could I just switch these out with my other 86? Also what kinds of things could cause this. I am back to getting around 7 mpg. (12 freeway woohooo). It has been running alittle bit better since I have ran it through a tank of gas, But as long as it is eating it that much I will not be able to drive it(or get it to pass emmisions) until I get this taken care of.
Title: Re: black exhaust.
Post by: V8Demon on June 06, 2005, 08:55:39 AM
OK, your vacuum lines are all connected.....Are they all in good shape?  No cracks or holes or anything like that?  As far as the EGR and EGO codes you should have no problem swapping the parts from your other 86, but if your runnin that rich I would have to say something else is amiss as well....I'm gonna say it's most likely your FPR or an injector....
Title: Re: black exhaust.
Post by: Clayton on June 07, 2005, 02:16:07 AM
Quote from: Paul Flockhart
I'm gonna say it's most likely your FPR or an injector....


i vote on the injector .......pull the injectors and clean them with a toothpick or a small allen wrench

as for the black exhaust..... im not 100% sure what is wrong with that besides maybe your cats are clogged
Title: Re: black exhaust.
Post by: Ifixyawata on June 07, 2005, 02:19:15 AM
I vote for FPR- Fuel Pressure Regulator.  Perhaps it's stuck or something and is giving the injectors the full 30-some PSI.  This will DEFINITELY cause the extreme rich condition you are experiencing.
Title: Re: black exhaust.
Post by: Tbird232ci on June 07, 2005, 09:49:21 AM
the injectors run on 37psi if i remember correctly

theres no real way to check a CFI regulator other than swapping it out

check the vacume line to the MAP sensor
Title: Re: black exhaust.
Post by: Haystack on June 07, 2005, 11:28:54 AM
its sefi. Thanks for all the replies. After all of those no starts on the car I assumed that everyone was ignoring me
Title: Re: black exhaust.
Post by: TurboCoupe50 on June 07, 2005, 03:40:19 PM
Your overly rich cond is likely one of three or four things.

MAP sensor, the vaccum line to it, or maybe its electrical connector.

F/P regulator, either pressure is high or maybe the diaphram is leaking.

Failed temp sensor causing the EEC to think the engine is cold.

The temp and MAP sensors will throw a code if they are defective.
Title: Re: black exhaust.
Post by: Haystack on June 07, 2005, 04:00:18 PM
map sensor dosent seem to make a diffrence weather it has the vacume line on it or not. I tried this last night.
Title: Re: black exhaust.
Post by: Bird351 on June 07, 2005, 04:10:37 PM
it, now I gotta deal with this problem, too.. since you brought it up. :p

I noticed that the new (patchwork) exhaust I put on my '86 got black really quickly.. within days.. and even puffed out tiny black puffs once or twice early on. (not consistent smoke coming out, it was kinda like when a smoker takes a drag and exhales and then starts talking and the first couple words come out with little puffs of smoke) I don't really know what I was thinking at the time, but I thought maybe it had something to do with me swapping out for the pounded-out cats from the '88, and disregarded it.

My CFI's FPR was drilled out by someone servicing the car for the previous owner. I can only guess that they also turned it up a bit, perhaps to try and cover for some other fault. I don't know. I also haven't found any vacuum leaks yet, but the car does vibrate a little more now at idle than it used to, so maybe I let a vacuum leak happen when I yanked the emissions stuff. (kept EGR and the charcoal canister, eliminated the cats and the smog pump tubing)

I guess I will have to ask AutoHole to pull codes or something, since I don't have a Check Engine light on that car.. and my multimeter is a digital readout.
Title: Re: black exhaust.
Post by: TurboCoupe50 on June 07, 2005, 07:35:39 PM
Quote from: Haystack
map sensor dosent seem to make a diffrence weather it has the vacume line on it or not. I tried this last night.


Swap it, possibly has a internal vac leak.. It should make a HUGE difference with the vac line off(assumin' there is vac on the line).
Title: Re: black exhaust.
Post by: ipsd on June 08, 2005, 02:08:53 AM
I also vot for the FPR. From what I find most of the time the ruuber piece gets a hole and you suck fuel right into the intake. just think of  how much extra gas that is at 30 psi. any how hope this helps
Title: Re: black exhaust.
Post by: Haystack on June 10, 2005, 01:38:28 PM
where exactly is the fpr on a 1986 5.0? I hav looked through my hays and still not found it....
Title: Re: black exhaust.
Post by: V8Demon on June 10, 2005, 01:48:23 PM
Located on the back side of the fuel rail behind the upper intake.
Title: Re: black exhaust.
Post by: nirvanagod on June 10, 2005, 02:05:25 PM
Is it just me on a Dayquil high, or is that picture backwards/forward/backwards??? It no looky right :dunno:
Title: Re: black exhaust.
Post by: V8Demon on June 10, 2005, 03:30:14 PM
That's how it shows in the Chilton manual.  Guess they just used the pic for the full sized Ford cars with 5.0 motors that have the intake situated the other way.
Title: Re: black exhaust.
Post by: Haystack on June 10, 2005, 05:33:07 PM
hey cool thanks. I figured that it would be a big thing along the fuel lines. Not alittle can sized thing. THanks paul
Title: Re: black exhaust.
Post by: Haystack on June 14, 2005, 10:17:37 PM
I am switching out the fpr with one from a wrecked car at the junk yard tommarow. Just in case, What other cars use the same ones? Pretty much all of them with SEFI?