help - '91 won't pass emission test

[macarchie]

My 3L 2wd (+180k miles) failed the VA emission test the other day. The shop wants $800 for a "major tune-up" which they say includes new plugs, wires, distributor cap and fuel filter. They also said they would adjust the timing. I told them no. The truck is running great and I don't want to mess around with something that ain't broke. I went to stick my timing light on it, but couldn't find the timing scale. (the little reference marks that are usually located beside the front of the crankshaft on the driver's side). Any idea where this scale is? I'm the original owner and have never had to have the timing set. The book says the base timing is set at the factor and the timing advance is controlled by the ICM. Which means it should never need to be touched - unless it is removed which it hasn't been.
I'm going to replace the air filter and PCV. Also put in some injector cleaner. The test results indicated that the O2 sensor and cats were working okay. Any ideas? What else needs to be changed. Do the plugs need to be changed even if it is running good?

Thanks for any help...

- Jimmy

 

[Mutant Pony]

What was the reason it failed? When was the last time the plugs were changed, fuel filter? If your cylinders have excessive blow by, a tune up won't help.

 

[almostclueless]

800 bucks for that stuff is ridiculous anyway.

 

[michowski]

Take the plugs out and see how they look. If theres carbon, or there really burned then replace em. If they just look a little dusty then there fine. I would replace your cap and rotor, pcv, wires, and put about a half tank of premium in your tank. Then let the computer retune for that gas, then put unleaded back in and go straight to emmissions. Premium runs leaner then unleaded so when you bring it back your truck will be running leaner then normal and should be enough for you to pass. Its worked everytime ive seen it done.
________
GL1500

 

[macarchie]

She failed due to slightly high hydrocarbons and CO. It has been several years on the plugs, but the one I pulled had a very light white coating (which I think is what we want).
Never thought about resetting with premium fuel. I'll try that after the other changes.

- Jimmy

 

[Psychopete]

800 bucks for that stuff is ridiculous anyway.

+1

I paid $250 for a fuel filter, oil filter, oil, spark plugs, front shocks, rear shocks, wheel bearings, rotors, front pads, rear pads, spring kit, caliper pins, brake cleaner, PB blaster, and the blue roll of shop towels. Took a couple of evenings to get it all done, but I think I saved quite a bit on money in the long run.

Pete

 

[macarchie]

update:
Went out this morning and purchased new plugs, wires, rotor, dist. cap, PCV, air filter, oil filter treatment and fuel injector cleaner. Total cost ~$110. Took about 3 hours to install. Just got back from test drive - she ran like a champ. I reset the computer (based on the instructions in manual) and noticed that the idle has changed from 1500 rpm to 1100 rpm. I suspect it will pass now - I'll take it down next week.

If this works, I figure I earned myself about $150 / hour this morning.
- Jimmy

 

[Richard]

set your idle and timeing to manafacture specs. it should be on your hood, a light grey sticker. and don't take it to a smog shop that takes your keys and drives your truck to the work bay and tells you to sit in the waiting room. take it to a small independant shop, where you can watch, just stay out of his way. don't forget the o2 senser.

 

[fordwheelinman]

I personally take offense to that Richard. I work for a Ford dealership and thats the way we always do it. We take the keys, pull the vehicle in, do what needs to be done, test drive, and park it. The customers wait in the waiting room and when we are done, they are told. Do you think just because we dont let the individual into our personal work areas that we are gonna screw something up or do something that doesnt need to be done? If they want to watch they are more than welcome to from the service desk. It is agaisnt OSHA and our insurance providers policies to have customers in the shop area. So SHOULD we be breaking the rules just because someone thinks we are cheats???

 

[Richard]

Smog

I did'nt meen to offend any body, sorry if i did. if you have a new car that needs to be smoged then the dealership is fine. but when you do your own wrenching and your car/truck is a few years old then theres no reason to take it to a dealer/stealership. (no offence to anybody)

 

[fordwheelinman]

Im not saying people shouldnt take their car to an independent shop, im simple asking if you think me and my co-workers are crooks because we do not allow people in out work areas, and that we like them to sit in the waiting room. Thats all. It bugs me when people stand at the desk looking at me every minute im working, its like they think im incompetent and im gonna screw up.

**i appologize for hijacking the thread, it just irked me**

 

[macarchie]

Hey guys...
The sticker says that the idle is set by the computer and cannot be adjusted. Likewise, the timing "advance" is controlled by the computer. It is possible to adjust the "base" timing (the timing at idle). I pulled out my timing light and couldn't find the timing scale (usually located near the front of the crankshaft on the drivers side). Any idea where the reference scale is?
As far as taking it to an independent shop. We only have a handful of shops around this part of the county that do the emissions test. The problem is that the shops that do the testing also do the repairs. They say they loose money on the emissions test, so they have to "find" something that needs to be fixed to make up the difference. The last shop I went to, shut the hood on one of the diagnostic connectors. If these guys can't get something simple (like closing the hood) right, how in the world can they rebuild an engine or complete any complex job correctly? Undoubtedly, we have all had experiences with good shops and bad shops. Some are incompetent and some do a good job. I guess the few good shops we have around here get enough work so they don't have to mess with the emissions testing... too bad for us.

- Jimmy