Phoenixsheperd

car is around 100xxx , 3.8l engine

I'm honestly at the end of my rope.

I went to emissions once.. failed all 3 gases..

now went to emissions a second time after repairing some of the vehicle.. failed on 2. Test result as follows

Hydrocarbon -->mine: 1.90 | applicable standard: 1.60
Carbon monoxide--> mine: 11.29 | applicable standard 15.00
Oxidies of nitrogen--> mine 3.23 | applicable standard 2.50

I have replaced the spark plugs, the spark plug wire set, changed the oil made sure the tires were aired up. put premium gas.. ran it hard for a day or two..refilling the premium, as well as the Ignition control module and coil.

was pulling 2 codes previously on OBD1 that was the electronic spark timing. which is now gone.

and the odometer which I'm aware of.

I'm wondering if it's because I put premium.. or the computer got reset... or maybe the CAT? I've been at this for months. first it was electrical with the connector that i fixed.. the car was sitting previously for around 3-4 months.

What can I do?! please help I'm at the end of my rope trying to get this thing to run properly.. shes my point a to point b vehicle Atm.

any help would be greatly appreciated!

pavemobile

Try a bottle of Redline Si-1 fuel system cleaner or Gumout High Mileage with Regane in a tank of fuel (run that tank as low as you dare the refill), clean your throttle body, check PCV valve. By your test readings it sounds like combustion inefficiency of some sort; if you can, try to see if carbon is very thick on your piston tops.
There is also Kreen which is only available from Kanolabs.com (I'm not affiliated) I have used it for fuel and crankcase cleanups and it does an excellent job using as a piston soak to breakup/dissolve excessive carbon buildup; quarts are the least costly to ship. After all your work, disconnect the battery for 30 minutes or use a diagnostic tool to reset your ECM and give it go. Good luck.


Edit - Almost forgot, how fresh are your O2 sensors? Replace them after all your cleanup work.

gs72

X2 on o2 sensors. If they are original or old they get lazy. I have a Nissan that would not pass smog. Look up cleaning cat converters with citric acid on the net and you tube. You mix citric acid (powdered for canning tomatoes) an oxcolic acid (don't know if I spelled that right) found in wood bleach (deck cleaner) in the proper ratios. I bought a big cheap stock pot mixed it in there, put the cat in it and simmered it on my gas grill for 12 hours. It made it work like brand new again.

Professur

Gotta ask .. where the hell are you that they emission test a 30 year old car?

joe_padavano

Well, if "Phoenixsheperd" means he's in Phoenix, that would be why...

How well is your catalyst working? The outlet temp of the cat should be about 100 deg F hotter than the inlet temp for a cat that is working properly. Use an IR thermometer to check this.

jcdynamic88

don't forget to check fuel pressure,a little too much pressure can raise havoc with emissions or if the pressure regulator is passing fuel

Phoenixsheperd

Looks like I'm going to have to check the fuel pressure regardless seeing as how I was running it the last few days and it started to sputter and die... left the key in the ON position, and tried to push in the fuel pressure dillibob and it drizzled out it didn't even spray like it should've.. somethings got it clogged. Great..... + the cat looks like it could be changed... back to the drawing board fellas.

going to drop the tank this weekend see what the hell is going on.

jcdynamic88

whenever you are diagnosing a fuel injected engine the fuel pressure should be checked,not enough or too much can occur and the engine may run but not right.the fuel pump is capable of a lot more pressure than the system requires.has the fuel filter ever been changed? i would check the pressure before you drop the tank

Phoenixsheperd

I have changed the fuel filter not long ago, (within 15,xxx) miles

The fuel pressure rail where you can put the gauge I pressed that in and found the gas drizzling out versus shooting out... it already is giving me a sign its got a low pressure buildup. I've been very meticulous about running this car, to date I have (myself)

changed the spark plugs (iridium) spark plug wire set, the shocks, the oil (synthetic) and filter, fuel filter, ignition control module, ignition coil, the connector to the ignition control module, all the bulbs. and even put new tires on this somabitch. engine is around 100,000 miles (odometer stopped working at 68,xxx (Not rolled over), put new hoses for the vacuum lines. (unfortunately the AC has stopped working- lack of freon maybe? ) the radiator is new since I bought the car as well as the compressor being converted over.

This car has still been dying, I'm honestly fed up with this car, when she drives I love her nothing like butter when she steers, and the v6 is a nice little pep for this car. but when shes sitting I can't stand it because it's all or nothing.. rarely symptoms nor even a light that comes on.

I'll try to use the actual gauge, but I have a good idea it's in the tank, or atleast the voltage going to the fuel pump (i can hear the loudass whine when i get it in the on position but not every time.)

jcdynamic88

your original post was related to emissions failure,now you mention it's dying,you may have more than one problem. a loud fuel pump can be early sign of failure.you really need to do a pressure test;key on engine off then running and also pull vacuum hose off pressure regulator while running to see if pressure goes up.these engines were somewhat known for bad crank sensors causing intermittent stalling and restart.there is no check engine light/code for fuel pressure issues.

Phoenixsheperd

Thanks for the tip, oh and early on when I had issues I did replace the crank sensor but it could've already gone bad.... as far as I can tell since the beginning of having this car (and I've checked most the wires so far. (starter wires is what's concerning) it has had some type of electrical problem seeing as how all the relay's under the hood are practically burnt (melted plastic by the end of the wires... grimy and built up), I also know the ECM on this vehicle typically has problems..... (why the sudden shut offs on the road -.-)

now as far as I've gathered based on the information you guys have given me (which is sincerely appreciated btw!)

it seems it could be an issue with the fuel pump, which I plan to drop this weekend and see if that will fix the car otherwise I will consider selling it, (and no don't worry I wouldn't do some shiesty *** sale, i'd actually prefer to give it to someone who can actually have the time to give her some TLC - Tough love and care.)

I got lucky enough to realize I have current tags until October,(don't ask.. serious knucklehead moment) however, that only lets me know I still have an emission problem that will be due in october, and as far as I can tell A new cat alone is 3 pieces including the muffler seeing as how it was welded before and it's so damn old I would want to replace the entirety of it vs just the cat (I thought it was gonna be a simple plug in play cat similar to new vehicles based on what I found with a lot of the parts... welll nope!) also I can hear what sounds like a crap ton of debris in the muffler when I keep giving it a good shake.. so whole piece replacement would be Ideal. I'll try to post a link to a video over this weekend to give you guys a better picture.

I would love to have this car to work on over the weekends and bring her back to life as best as I can, I truly will miss this car when it's quits, but unfortunately she is my point A-to-B vehicle to work and I rely on rides from my family now since it's sitting again....... leaves me with limited options -.-

Heres to hoping this weekend dropping the fuel pump can give me more time with her.

Thanks for the help gentlemen.

joe_padavano

Replacing the cat with a universal one is easy. Cut the pipes on either side of the old cat. Install the new one using band clamps. Takes about half an hour. I did this on a P.O.S. Pontiac Grand Prix I once owned.

jcdynamic88

the crap you hear in your muffler just may be what used to be inside the cat,if this is the case and a piece gets lodged in the outlet of the muffler it can shut the engine down.