CA Smog Test

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LeslieO
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CA Smog Test

Post by LeslieO » Sun Dec 16, 2007 1:41 am

My 85 XR won't pass the smog test. I have been living in KY for a few years where they don't do smog tests, but before that it passed in OR and CA. I have new spark plugs, cap and roter, cleaned the vam and everything else I could, had the timing checked and adjusted, and put fuel additive in to clean the injestors. Also have a brand new catalytic converter. It passes all the visual stuff, and the new ( as of Dec. 1 ) fuel system check ( for leaks). It fails the HC(PPM) and CO% at both 15 and 25 mph. They told me to take it to a smogcheck station that also works on the cars and gave me a list of state approved shops around Citrus Heights where I live. Oh, I also have a code reader and it said NPS failure during the first part of the test, and loss of tachometer input/IDM circuit failure/SPOUT circuit grounded. Could any of these be affecting the emissions? The tach works, by the way. The smog guy told me the emissions were WAY off, not just a little. Does anyone have a recommendation for a smog repair place near me? I am so afraid to let someone unfamiliar with Merkurs work on my car, but I have done all I can and I WANT TO DRIVE MY CAR! It drives so nicely now as I also have a new clutch, throwout, clutch fork, guibo, shocks, struts and frontend bushings. Thanks for any advice you can give me.
Leslie, a gal who loves her car!
85 xr4ti owned since 89
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Slinky
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Post by Slinky » Sun Dec 16, 2007 6:17 am

Leslie, I'm not very good with smog diagnostics but, I can recommend a shop to you.

StreetTech Auto Care
8820 Greenback Ln
Orangevale, CA 95662
(916) 987-1500

They are tucked away on the corner.

There's a older gentleman that works there that has 3 XRs, he hasn't ever done any work for me but said come to him anytime for parts. I'm not sure if they are smog certified though.

Let us know what happens.

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John R. Rowlands
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CA Smog Test

Post by John R. Rowlands » Sun Dec 16, 2007 11:21 am

LeslieO,

Let me suggest that you do it yourself! Not that complicated. First I would suggest that you change the oxygen sensor. It sticks up from the elbow on the back of your turbo charger. It has a single wire running from it and it's probably a nasty looking chrome color. It will also be real tight so you may need some help getting it out.
Next: On the curved part of the intake manifold there's a big hose that comes off and goes down the right side of the engine (as your facing it from the front) follow that hose and you will run into a little plastic valve. Thats your PCV valve, change it.
The Next one, the hardest: The EGR valve. On the back of the upper intake, the round part, is the EGR valve. You will want to clean that. There is about a one inch tube coming from it running to the exhaust manifold. Put a wench on the nut that the tube goes through and try to unloosen it. DON"T let the wench slip because you don't want to round the nut. It it won't break loose using a regular wench, use a small pipe wench on it. After the tube is loose you may have to pry it out of the valve. Don't bend it to much. Now the easy part. Unloosen the two bolts that hold it to the manifold and take it off. Now the fun part. You will need a 1/4" combination wench to take the three bolts out of the valve. The valve is spring loaded so be careful that you don't loose the tiny bolts. Use some spray carb cleaner to clean the valve You are going to have to scrape a lot of the carbon off but it will come off. Clean and reassemble everything.
That should get you through your emissions check.
If you have any questions ask away. One question for you what was the first code you got when you ran your code reader scan?

You can do it, not that difficult

John
If it ain't broke don't fix it!

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LeslieO
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CA Smog Test

Post by LeslieO » Sun Dec 16, 2007 12:06 pm

Slinky, thanks for the info on the shop, I will check it out. John, the first code I got was 67, then a code ten which I understand means the reader is finished with one test and moving on the the second test. After 10 I got code 18. If I read the manual that came with the reader correctly you have to fix the first code, and then run the test again for any more codes. So I don't know if that means to disregard the second code for now? I wasn't planning on fixing the nps at the moment, and I am not sure when it went bad because I always push the clutch in and put the car in nuetral to start it anyway. I was assuming since the code reader didn't mention the oxygen sensor that it was ok, is this a bad assumption? I am willing to do all those things you mentioned but I don't want to buy parts if I don't need them. Also, I have listened for vacuum leaks but I don't have any better way to check for them, could a leak be causing my smog problem? The smog guy said unburnt fuel is coming out of the tailpipe. Thanks for all the advice.
Leslie
85 xr4ti owned since 89
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John R. Rowlands
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CA Smog Test

Post by John R. Rowlands » Sun Dec 16, 2007 12:24 pm

LeslieO,

The code 67 is the neutral safety switch, won't have anything to do with the smog test! Code 10 I don't list in my book, are you sure it was a code 10? Code 18 will not effect the smog test either.
How did you run the engine scan with the key on engine off (KOEO) or with the key on engine running (KOER)?
If you ran it KOER and didn't get a code for the oxygen sensor then it should be OK. If not run the scan KOER and see what codes your get. If the oxygen sensor is OK then the PCV valve and carb cleaner should be less the $10.00.

Let me know!

John
If it ain't broke don't fix it!

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LeslieO
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Post by LeslieO » Sun Dec 16, 2007 12:33 pm

John, I ran the KOEO test. Now that my timing has been tuned I will run the KOER test and see what happens. The code 10 is not a real code, it just lets you know that the KOEO test is over and the continous memory test is starting. Anyway, that is what the book says.

Thanks, Leslie
85 xr4ti owned since 89
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Post by milehighXR » Sun Dec 16, 2007 12:37 pm

Code 10 during KOER test means mash throttle to floor for TPS check. The comp must see WOT. If not TPS is either misadjusted, or needs replace.
Johnny


1 86 XR aka Naomi- my first love, now project car
1 14 black Fiesta SE aka Fiona- my new DD

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LeslieO
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CA Smog Test

Post by LeslieO » Wed Dec 19, 2007 1:12 pm

Update: I followed all the suggestions, cleaning valves and a new oxygen sensor and pv valve. I still have emmisions that are way too high. It seems every time I do some cleaning or buy a new part I am rewarded with even more unburnt fuel coming out of the tailpipe/car running richer. Yesterday I took it to a shop that is cerified by the state to smog and work on the cars. They said 2-3 hours to diagnose the problem. They had the car all day yesterday and they still have it. Fortunately they are not giving up and aren't charging past the quote, at least so far. I am not sure of what tests they did so far, but I overheard them say the compression was good. Could a bad fuel regulator cause this? Computer problem?
Thanks for any ideas you may have,

Leslie
85 xr4ti owned since 89
One Black One Maroon

yottabit
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Post by yottabit » Wed Dec 19, 2007 1:41 pm

Could be a stuck fuel injector?

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DPDISXR4Ti
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Post by DPDISXR4Ti » Wed Dec 19, 2007 2:07 pm

Do you have the emissions output report? That will provide some guidance on what the cause is.

Have they dumped trouble codes yet? That's not foolproof, but it's a good place to start. It will also confirm that the PCM itself is working and not the cause of the problem.
Brad

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LeslieO
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CA Smog Test

Post by LeslieO » Wed Dec 19, 2007 5:38 pm

The repair shop just called and said I need a new computer. They said they checked everything else and it all checked out. They said the fuel injectors were working fine. The emission results on the last smog test are for HC, 204@15mph and 181@25mph, and for CO%, 7.71@15, and 7.40@25mph. They weren't quite this bad to start but get worse each time we check it. So, is process of elimination a good way to assume the computer is bad? Or is there a better way to check it? I have a code reader, but if the computer is bad can the code reader still work properly? In any case, I am going to bring the car home for now. Can I install a new computer myself? The shop wants to charge $60 for labor and $264 for the computer.
Also, this motor was rebuilt several years ago by a shop that mostly does racing engines. They had to bore out the cylynders, and at that time they replaced the injectors. I don't know if they used stock injectors or slightly bigger ones. Would it affect the air fuel ratio if they had used bigger injectors but the stock MAF still on the car?

Thanks, Leslie
85 xr4ti owned since 89
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Post by DPDISXR4Ti » Wed Dec 19, 2007 5:52 pm

In no particular order....

1) Generally speaking, a good PCM will allow you to dump codes, a bad one will not. So yes, that's the easy way to test them.
2) $264 is way too much. You should be able to pick them up for $20 - $40. You just need to find the catch code - probably PK1 or PF1
3) Given that your output numbers aren't that far off, I doubt however that the PCM is the problem. I suppose it could be worth swapping if you can get one for ~$25 - it is easy to do.
4) If bigger injectors were installed with no other changes, that could indeed be the problem.
5) Your car doesn't have a MAF, it has a VAF meter. Frankly, these ARE prone to getting "tired" as they age, so if I was going to try the parts-swapper route, I'd probably try one of those first.
Brad

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John R. Rowlands
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CA Smog Test

Post by John R. Rowlands » Wed Dec 19, 2007 9:42 pm

LeslieO,

I agree with Brad I don't think it's the PCM either! As was stated you can get a used PCM at the local junk yard for $20-$40.
To get to the PCM: On the passenger side of your XR there's a kick panel right above where you put your feet. Remove this panel. Stick your head up under there an look for a silver box about 8 inches square. Pull down on the front of this box (that's toward the passenger seat) and it will come out. That's your PCM. There's a big plug that has a bolt in the center. Unscrew the bolt and pull the plug and the PCM is out. PK1 and PF1 refer to the PCM's for the standard transmission and the automatic transmission.
Fuel Injectors: Look at one of your fuel injectors from the side. You will see the part that goes in the the manifold. Then you will see a plastic ring and then the inner part of the injector. That plastic ring should be BROWN if you have stock injectors. Big injectors alone, without any other engine modifications, will affect you A/F ratio. Another way to check this would be to pull one of your spark plugs and see what color the insulator is!
Again! run a KOER test and see what codes you get.

John
If it ain't broke don't fix it!

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Re: CA Smog Test

Post by milehighXR » Wed Dec 19, 2007 9:46 pm

John R. Rowlands wrote:LeslieO,

I agree with Brad I don't think it's the PCM either! As was stated you can get a used PCM at the local junk yard for $20-$40.
John
Maybe in Kurplunkistan, but here in CO I have paid upwards of $100.00 for one. And almost all the yards around here want a minimum of $100.0 for ECMs.
Johnny


1 86 XR aka Naomi- my first love, now project car
1 14 black Fiesta SE aka Fiona- my new DD

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Post by thesameguy » Wed Dec 19, 2007 10:59 pm

I have a spare automatic ECU you're welcome to borrow... I had one from a 5-speed that I thought I gave to Slinky, but neither of us can find it. I think the automatic one will at least run your car - others probably know better than I. If it'll work, you're more than welcome to borrow it - I've been trying to ebay it for eons! :D

High CO + high HC is usually the result of a pretty rich mixture. That's gonna be either a misbehaving injection system or a worn out ignition system - assuming compression is good. The O2 sensor is a solid place to start to get that back in tune, since you've done the other basics. You should also consider your plug wires, air filter, PCV system, oil, and fuel pressure regulator. Injectors are also suspect - and I find it weird that they can clear the injectors without an ECU that's working properly... I have a set of 6-month old plug wires you're welcome to if you want them - they're cheapo Autozone (Duralast?) brand, but they got my car through smog. I replaced them with Magnecors, so they're not doing me any good.

I'd be cautious about driving it - if the system is indeed "way off" and you're running really rich, you can foul your brand new cat pretty quickly... that sucks, 'cause even if you fix the problem you may still not pass without replacing it - again.

Oh, also, I dunno about XR4Tis, but on Bosch-injected cars a bad coolant temperature sensor can also cause the issue. It keeps running cold enrichment even when the engine is warm. I'm assume EEC-IV has a similar component, but I've never paid attention.

I think Slinky's recommendation for a shop is excellent, but in the end anyone familiar with an '80s Ford should be able to fix this issue. I've got a local guy (East Sacramento) I deal with - he's slow, but eventual, and totally fair. He's also a smog shop, which is convenient.

I can't think of anything else at the moment... good news is that HC/CO problems are much more easily fixable than NOx issues, so that's on your side. ;)

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