Running rich, failing emissions

[boomienutcake]

So I've been tinkering and trying to pass emissions here in AZ for the past 2 weeks, I'm running very rich. My first test kicked back %5.98 CO at idle (%1.20 standard) with 449 HC (220 standard). I immediately went home with a can of starting fluid and sprayed around for vacuum leaks, found and fixed a couple of pretty big ones. For the second test, I changed plugs, swapped out the O2 sensor (carboned up and leaking, tested intermittent), reset ecu and timing, bumped up to 91 octane with additives, and ran through with %3.00 CO and 460 HC (higher?).

A few months ago, my fuel damper sprung a leak. Little did I know LAST year (changed head gasket, passed with flying colors), I was poking around without any knowledge of the engine and ended up unscrewing the factory set adjustment screw at the top of it, came to a seemingly endless screw, and jacked it back down ALL THE WAY. Anyway, I've somewhat traced my problems to the pressure regulator, though I have no way of pressure testing the fuel rail, so I'm not completely sure. Is there a sure fire way of knowing if the FPR is indeed the culprit? The air nozzle isn't leaking any fuel. Could the leaking damper be causing my rich condition? Could the leaking damper have botched the FPR?

Any help appreciated, I have 3 days including today! :1zhelp:

 

[jdub]

Did you check for codes?

Check the cold start injector to make sure it is not stuck open.

High HC & CO mean unburned fuel/incomplete combustion.
- What did you gap the plugs at?
- Did you check the plug wires?
- Is there any kind of misfire?

Any exhaust leaks pre O2 sensor?

The FPR could be a contributer, but I doubt it's the main problem.

Your CAT could be the problem as well...running rich for a long time will trash a CAT.

 

[boomienutcake]

No codes. Good idea on the cold start injector.....maybe I should add that the engine only seems to be bogging out when coming back to idle after it has been warmed up.

I did replace a couple of plug wire ends with broken rubber boots where they mate with the head, could have been arcing out, and may have contributed to my lower CO second time around. Plugs are gapped at 1.1mm, and besides coming from a rev to idle, runs and idles smooth as glass, but smells foul. I also did tighten down my exhaust, the entire back side was loose. I'm just afraid to head back for test number 4, I don't want to be whacked an EXTRA $12.25 for nothing, caught me by surprise the last time.

 

[jdub]

Check the air adjustment screw on the top of the TB...it should be screwed completely closed. Might want to replace your plug wires.

The exhaust smells like rotten eggs? That's a bad CAT
You will have to replace it.

Go to PepBoys and get a bottle of GumOut Regane (clear bottle, gold liquid) and pour in your tank. Drive for a couple days.

Get a gallon can of methanol (or denatured alcohol) at Home Depot and pour in the tank (1/2 or less full) for your next test. Run the car on the highway for at least 10 minutes before you test. Afterward, fill the car up with gas to dilute the methanol.

 

[boomienutcake]

Okay, so I just went out, disconnected the electrical connector on the cold start. The ohm readout is at ~4.1-4.2 across the two terminals. Close enough for spec you think? I did leave it disconnected and let her heat up, ran at around 1100 rpm the entire drive, but once I parked it, it slowed down to around 700 rpm and continued it's rev to idle bog, but showed no such signs during the drive. The TSRM states 2-4 ohms... are those numbers measuring the gap in the valve? and you mean TB, as in turbo? I have an N/A.

The exhaust doesn't exactly smell like rotten eggs, more just like a really rich mixture. The cat is only a little over a year old. My friend (previous owner) had his old one plug up on him. Are you suggesting the additives to clear out whatever might be hanging an injector up?

 

[boomienutcake]

Alright, I just went out and pulled the high tension spark wire, held it about a half inch from the front fender and had my bro crank the engine for a few seconds. I'm getting an orange spark from it.....would you say weak? I can't check the resistance at the coil because I can't figure out how the darn connector plug pulls out, hahah.

 

[jdub]

GumOut Regane is one of the few effective injector cleaners out there...Chevron Techron Concentrate is another...they both contain polyether amine (PEA) in a concentration that actually does some good. Red Line SI-1 has PEA in it as well.

TB = Throttle Body. If your idle is surging, you have a pirate air problem...did you check the TB screw closed like I said?

The CSI can check out electrically, but be mechanically stuck....it would have to be removed for a clean/test.

The CAT was new or used when it was installed?

Don't test the coil spark like that...use a spark plug that's grounded. You want to test wire resistance.

 

[boomienutcake]

I wasn't aware that there was an adjustment screw on top of there...there doesn't look to be anything like that. Are you talking about the dash pot?

Cat was brand new, I'd say replaced February last year.

I was testing it via the TSRM method. Checked wire resistance, only 16 k ohms.

 

[jdub]

The early TBs usually have that screw...and, it's usually been messed with. Later model TBs did away with it. I assumed yours would because you have an '87...if it's not there, that's actually a good thing.

Yes, I know what the TSRM says on the spark test and it appears yours is good...arcing to a body part is not a great technique IMO. Are all the plug wires at that resistance? If so, it looks good.

Did you test the coil?

Did you check timing?

Back to the original question...the best way to test fuel pressure is here:
http://www.cygnusx1.net/supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=71

 

[AJ'S 88NA]

The screw on the TB on mine, 88, has a 1/2" black plastic cap on it on the front of the TB. The screw is behind that.

 

[boomienutcake]

Okay, coil reads primary resistance at 1.2 ohms....WAY high? Secondary is 11.24 k ohms.

Thanks AJ, that's sounding a little familiar, I'll go out and see what's up.

 

[jdub]

Just so you see where I'm going...High CO and high HC are not normally related. In this case, a rich misfire can cause both high HC and high CO readings though.

High CO= Rich condition, CO is partially burned fuel
Causes
-High fuel pressure
-Leaky injectors
-fualty temp sensor
-thermostat stuck open
-clogged air filter
-charcoal canister full, fuel to topped off, faulty purge
-Fuel in the crankcase

High HC= incomplete combustion
-bad ignition, coil, plugs, wires, cap, rotor
-over advanced timing
-low compression
-stuck EGR

So far, I've been mostly looking at the HC side due to the possible misfire. High HC will kill a CAT, especially if the car is run mostly on short trips.

 

[jdub]

Yes, that primary coil resistance is way high...the secondary is pushing the top limit.

Is there a coolant thermostat installed? What temp rating is it?

 

[boomienutcake]

Alright, thanks AJ, found the screw.

Tightening it all the way down made it run like a pig, exhaust smells like raw gasoline. Loosening, however, obviously leaned me out and made things smell better. So where do I stand here, hahah... (?)

 

[boomienutcake]

Thermostat is installed, I believe it is a 190.

 

[jdub]

Pull the EFI fuse for a minute and turn the screw all the way in. Give it another start.
The ISCV and PCV lines should be clear...blocking both off should kill the motor.

What does your coolant temp gauge read after warm-up?

Do you have the EGR installed (I assume you do)...what was the NOx reading on the last test?

 

[boomienutcake]

Still runs just as bad, so I opened it back up to standard rpm to keep it idling. Temp sensor is at .347

 

[jdub]

Still runs just as bad, so I opened it back up to standard rpm to keep it idling. Temp sensor is at .347

Does your ISCV open when you shut the motor down?

What does "Temp sensor is at .347" mean?

 

[boomienutcake]

I do hear a click coming from it.

Sorry, got ahead of myself on that one. The dash reads dead center on the temperature. The coolant temp sensor on the outlet housing is giving me an accurate resistance level, thus the .347 k ohms...

 

[jdub]

Ok...so, the coolant is warming up....that's not it.

It does sound like your coil is bad.

Have you set timing per the TSRM?

The idle concerns me...the ISCV controls idle on this motor, that's why the screw should be all the way closed. You might want to pull the ISCV and clean it...you'll have to remove the 3 screws attaching the motor to the base. Clean the valve set and the lower housing.

Another thing to check is the EGR valve...the TSRM has the procedure.