94 ST 7A-FE, 3 quarts of oil and misfiring. Options

[Steevo]

Hi!


Let me just start out by kissing everbodys feet.



I have come into possesion through marriage (told her I would get it) of one of these nice cars.


But there are a few problems that I am having, other then her brother warping my new pressure plate and burning the clutch and taking out second syncro. Me and him and a piece of heater hose have a date in a dark alley.......


First off I have a mis-fire that is recurring but only between 2K and 4K RPM. It sounds just like the fuel gets shut off for a couple miliseconds, about every 10 seconds. I can also hold it at 5K or so and it will slowly increase RPM as it adjusts fuel mixture, that is normal. But when dropped back to 3K it starts dropping RPM untill the mis-fire is back.

I believe it is running too rich as I can wipe the end of the exhaust tip and go for a short drive and the light black film is back.

So far I have been advised by the "local" (50 miles away) to change the front O2 sensor, plugs, rotor, cap, wires, check timing, check fuel pressure, change fuel filter, etc.....

No dice.

Next problem is the missing three quarts of oil. Has anyone seen them? From every indication they haven't been burnt, but the belts have gotten wet from oil when I ran synthetic Mobil One through it, I changed to 10W30 oil. But it doesn't leave oil drips from what i have seen. It doesn't smoke. And it has only been 2,000 miles or so between changes.

I don't know if it is pushing oil out during driving or while the engine is running, and I honestly haven't had the time to check. I'm just looking for some insight here.


I used to turn wrenches on domestic stuff for fun and a bit of money, so that part isn't new to me. But these two problems have me perplexed.



Now for the good stuff.

1994 Toyota Celica ST Hatchback Rennisance Red
1.8Liter DOHC
K&N filter, larger PVC intake tube. (no laughing)
Corbeau Seats
Pioneer Premier System
Basic 200W AMP with a BOSE Acoustamass module
Napa clutch kit (she didn't want to spend the money for stage one puck clutch)
Custom dark black tinting.
Did have a short throw shift kit, but the bushings kept cracking, and the knob would come loose.
Changed tranny fluid from 75W90 to ATF for better shifting.
And I have a set of Pirelli P6000 on the way. Looking forward to burning up the no-names on it.

This post has been edited by Steevo: Jul 24, 2006 - 9:46 AM

[Bitter]

it really may be easier to just swap in a rebuilt 7afe or go nuts and make this a 7age :lol:

how fast do you loose 3qts of oil?
have you checked the crank and cam angle sensors (which ever is applicable to the the 7afe)?
have you checked for breaks in the wiring?
is or does the check engine light come on?

[celicaST]

welcome, cant help you, but where at in colorado are you from?

[Steevo]

Brush Colorado!!!! WOO!!!


No engine light, no codes, I checked.

It only does it at certain RPM's.


In about 900 miles of use.


I haven't checked the sensors yet, but it is going in the first of next month for a timing belt and checkup, so i will have those checked too. I politely declined putting the belt in, the clutch and other stuff was as much fun as I could handle.

[tomazws]

Same problem with you.

About loosing oil, mine was due to a leak at the screw on the underpanel. The rubber ring on the screw was melted and the oil just leaked from there.

About missfiring. Mine is only cylinder #4 (Check engine light actually came on). Changed spark plug wires, no help. Gonna put in some NGK spark plugs and see if it'll do anything...

[Steevo]

I would like to have the ECU sent in and have it turned up and ready for boost. I still believe it is a fuel problem. Plus I have a little IHC turbo here and it will fit upside down if I change the passenger side fan to a pusher fan. And the local machine shop have a mounting flange made friom stainless and the upper cat removed.

O2 sensor could be put back in the downpipe. Oil from the pressure sender back to the pan.

I have seen some people pushing 6-9PSI without changing any internals safely.

I would like to have the head CC matched and increased volume-smoothed for better flame travel, as well as a overbore and drop the CR to 8.5:1 but that has to be later. I am buying a house.

This post has been edited by Steevo: Jul 24, 2006 - 11:26 AM

[celicaST]

Brush Colorado!!!! WOO!!!

cool you arent far from me, im in loveland, not too far west of you on 34. for buying a house

[Steevo]

I was almost in your area, but decided I liked a bit more space.


Nuffin like a wide open road on a cool evening.

[sinner96ST]

swap out that ghetto PVC intake, i bought a short ram + cone filter off of ebay for like $15 shipped, literally. speaking of that, is the MAF sensor clean & at least secured inside this intake? that could be your problem, although it sounds like you're misfiring.

in terms of hard to find oil leaks, you could try a tracer dye kit. my money is on a leaky gasket somewhere. if your ST is high mileage, i'm sure some gaskets need to be replaced on it.

[Bitter]

i thought all the 7afes were Map.

[celicaST]

speaking of that, is the MAF sensor clean & at least secured inside this intake?

i believe you are referring to the iat sensor in the intake tubing. as stated above, 7afe uses a map (manifold absolute pressure) not a maf (mass air flow) sensor and that is located on the firewall with a tube to the intake manifold.

[Steevo]

Vacume' leaks ala mode'





Harr.




The PVC isn't visable, it is leading into the airbox. I took out some of the shielding to get it in.

[Steevo]

Checked all my hoses, vacume tubes, no leaks.


Reset the ECU, still does it. (misfires)

Still don't know where the oil went. Checked everywhere, only conclusion is is with the socks the dryer ate, or that it acutally did burn it, but it still makes no smoke, and the plugs are clean, but I only pulled one. So more checking later.

No time this weekend as I am going camping. A friend will have it to drive though.

[Steevo]

Just checked it over again before lunch and took it on a few runs.


0-60 12seconds on video, I don't know how this rates.
And some video, of 100MPH on a short run. Up and down a off and on ramp.


The sound on the video is crappy, but that is on a PC here at work. So I will check it later, plus me grinding some gears trying to shift, steer, and hold the camera. But I did get the misfire, if you can hear it. I ran it clean at 5800RPM then dropped to 3200RPM and it did it a few times.