View Full Version : Help with troubleshooting/codes

05-15-2016, 06:20 PM
OK guys, I'm gonna write you a small book for the history/issues on this one, be patient, and help me out!

The car is 1990 XR7 AOD auto, 93K mi. Basically stock till about a year ago (flowmaster cat back and custom cat down pipe, 10% pulley), when heater core let go on a 14 psi blast thru the gears :o. Figured either lifted the heads or gaskets failed and pressurized cooling system (was right, they were WAY distorted on removal). At that time I did some mods;

heater core
ported heat wrapped early exhaust manifolds
ported heads with stock valves performance grind/ARP studs (pressure tested, new seals, not sure on guides, were ported when I got 'em, but machine shop gave 'em the OK)
Fel pro standard gaskets (NOT multi layer steel)
ported/gasket matched intake
UN ported late model blower (minor flaking on rotors)
late model 36/38# injectors
10% blower pulley
MP blower inlet
homemade raised top
70 mm throttle body
73 mm C&L mass air meter/K&N/cold air intake (supposedly "matched" to late injectors)
double intercooler with fan (wired to run whenever motor is running)
AC delete w/NA mustang tensioner
MP springs and pullies on all tensioners
under drive pullies
Taylor wires and new plugs
new non liquid filled motor mounts (mustang?)
Oil cooler delete
stock fuel pump
same old exhaust

I have not had the car tuned in any way, other that trying to "match" parts. I know that I need to get a tune, I should probably be happy that it runs like it does without :rolleyes:.

It seemed very sluggish/disappointing with this combo, and I felt it was running rich. It has a small amount of "sooting" around the tail pipes, and a small black puff when free reved. I also felt the mileage was not what it should be, but what the hell, that's NOT why we drive these cars :D. 18-19" vacume at idle, 750rpm in neutral, 15-16 at 600 in gear, and 13 at 2000 [email protected] 65-75 . I never did get a tune. I also always had a very slight smell of coolant, especially when running the heater. It also lost a small amount of coolant over time.

When I pulled the car out this spring it ran like crap.... would barely start or idle. I DID have to jump start it from an absolutely dead battery. I BELIEVE it "learned" its base tune badly because of that. After getting a new battery and clearing the memory it ran better (same as when I stored it). Then I finally found a small crack in the radiator. That started me swapping parts.

Another car broke a rod last fall.... Another story 4 another time :rolleyes:, and it had a few better parts (5spd, ported late blower, 75mm t-body, 76 mass-air for 42# injectors, oil separator). It ran MUCH better than I felt the difference in combo should make between the 2 cars.

A new radiator cured the water loss and coolant smell, FINALLY. While doing the rad swap, I found a LARGE amount of oil in the top, intercooler, blower and plumbing. I know these cars are prone to sucking oil from the PCV system, but with the experience of several, and tearing down several more this seemed an EXCESSUIVE amount (most I've ever found in any car). So, since the other car ran better, but was broke.... I swapped the air shield (box) for the cold air inlet, the 76mm mass-air, and the oil separator.

The car REALLY woke up with these parts. Now I felt it was running as it should. No more black puff when free reved. The vacume #s were unchanged. I still have not had it tuned. After about a month, as the weather warmed up, It started throwing a check engine light, just as I parked either at home or work, after driving 15-20 minutes at highway speeds. Warm/hot starts also became hard, starts great when cold.

NOW. I am getting about a full cup of oil out of the separator every 300 miles, which I still feel is excessive (no sludge or creamy milkshake/moisture). The car has never, and still does not smoke, smell, or use an excessive amount of oil, and with the separator at least it isn't getting into the combustion chambers. Finally got around to checking codes today.

Key On Engine OFF;
#85 canister purge circuit failure (as listed in my tester book when read with engine off)
#85 Adaptive fuel limit reached, Lean (as a Continuous code)

This was read as an KOEO code NOT a continuous code. Continuous codes (keep alive codes/"permanent memory" codes) came back as 11, OK or no codes.

Key On Engine Running;
#42, and #92, both HEGO sensor voltage high, system rich.

The check engine light and system rich makes sense. The purge circuit, may indeed be bad, but I don't think it should affect rich/lean mixture? I plan to swap out a "known good" valve from another car as soon as I get a chance. The adaptive limit also seems to make sense, its rich, after trying for the 20 minute drive, it finally reaches the limit, but why would that not be a continuous code, NOT a KOEO? Rich, and limit reached both sorta make sense with the hot start issue and sooting around tail pipes/mileage as well. I have NEVER had a Ford O2 sensor fail high voltage, ALWAYS the opposite. Why a mass air meter that was supposedly for 42# injectors (and ran well/correct with them) would run rich with 38s is odd also. Basically I am confused as to why it would run great for 1-2 months, then suddenly act up? Does ANY OF THIS have ANYTHING to do with the excessive oil in the intake tract?

The oil in the intake.
I have swapped out PCV valve ("rattles" crisp and clean, only way I know to check). No change in the amount of oil. The only things I can come up with to cause this to be worse than normal (for these cars) is;

#1 bad ring seal. NOT getting any other signs, but have not done a compression or leak down test (you KNOW why :p)
#2 intake gasket leak. Again, NOT seeing any other signs.
#3 cracked head/intake.

So.... Any experts (hell, any crackpots :p) got some ideas that may help cut down the number of dead ends I have to run down here?

Thanks in advance, and sorry bout the length of the novel, but I figure too much info is probably better than not enough :rolleyes:


05-15-2016, 08:14 PM
I believe that for the SC, 85 is canister purge; continuous.

I'd focus on why you're collecting so much oil in the cup in so short a time....that and the top, etc, first.