Hello everyone,

I don't post here often since I don't know much about trucks except how much I love mine & want to keep him on the road. I have had problems passing smog ever since I replaced the block in 2003 (he overheated & it cracked & I'm positive the "new" block is why he fails smog now). I've had the carb rebuilt 3 times, the last time about 3.5 yrs ago. I thought replacing the intake/exhaust manifolds would fix the problem but he's running too rich. Hardly anyone works on carbs out here so the few that do can be pretty scary price wise. I'm taking it to a place that specializes in carbs so they can check it out & see if he needs to be adjusted or rebuilt. My regular mechanic can rebuild the carb but he can't do catalytic converter work, which he says I'll need based on the failed smog test. Thankfully I found a guy who can do a cat test & then tell me if I need it replaced & how much it will be, etc. He's a STAR certified mechanic so he can smog my truck as well. Has anyone had issues like this? I'm in CA so they make it harder & harder for my truck to pass smog (they'd prefer I just retire him but that's not gonna happen as long as I can help it). I know this is gonna be very pricey & I should've just bit the bullet last year but sometimes you have to learn the hard way like I'm learning now. Any advice would be appreciated. Thanks so much & I hope everyone is doing well with their trucks this weekend!

 

Subscribed.

I'll be doing smog this summer and what to see what will be recommended.

 

Welcome to FTE.

Sorry to hear of the troubles. An '86 with a carb would have a computer controlled carb.

Did you get a print out of your test results? If so, post the results.

We need the limits for each catagory, and then your results.

For example, if you failed for high HC, but your CO was nearly OK, you probably DO NOT need a cat. But, if your HC & NO were good, but the CO was off the chart, you probably DO need one.

Post it if you have it.

 

Smog problems were asked and answered in these threads, just for illustration purposes:
https://www.ford-trucks.com/forums/1...g-problem.html

https://www.ford-trucks.com/forums/1...mog-stuff.html

https://www.ford-trucks.com/forums/1...emissions.html

Also, this is how to read OBD I codes:

FORD 1983-1995 OBD1 Decoder

 

Hi! Thanks for the quick replies! Here is my test info:

Code:

            RPM     %CO2    %O2      
M1: 15mph - 1215     9.7    4.8
M2: 25mph - 1188    11.0    4.7

                        HC (PPM)
             Max    GP   Meas
M1: 15mph -  131    320   252
M2: 25mph -  103    270   199

                       CO (%)
             Max    GP     Meas
M1: 15mph -  0.61   2.17   3.40 (he registered Gross Polluter on that one) 
M2: 25mph -  0.77   2.40   0.86

                        NO (PPM)
              Max    GP   Meas
M1: 15mph -  760   2050   89
M2: 25mph -  784   2100   96

The guy who can do the cat said based on those numbers, the carb is running too rich & that is causing too much fuel to be dumped on the cat. I feel like a world class idiot for not just doing it last year but when your mechanic says it's going to cost a lot of money (which you don't have) & doesn't particularly want to work on it (he didn't say he didn't do cats) & you're unemployed, you skip things. This is now going to get REALLY expensive but I have to do it 'cuz w/out my truck, I won't be able to get to a job whenever I get one so I'm damned if I do & really damned if I don't. I'm heading out to have the SD Carb specialists check it out & hopefully it won't cost an arm & a leg for them to do it. My regular guy can do it for $375; once it's rebuilt or whatever, then it's on to the cat test & possible cat work.

Thanks so much for your help! Hopefully others can learn from my mistakes (I sure wish I was more mechanically inclined like the posters here). Wish me luck!

 

Your carb is computer controlled. If the computer is not working, it can mess up your carb and also the timing. I think instead of doing the same thing again, you need to take it to a Ford guy who plays with computers and wires. They may be able to pull some codes from the computer and tell if you have any bad wiring or a bad sensor. Your truck is almost as complicated as a fuel injected vehicle, only it has a carb instead.

 

I got your reply a few minutes after the carb guy had basically told me the same thing, lol. Great minds think alike He's got it hooked up to machine so he can collect the raw data & he's adjusting it so it won't run too rich. He said he got it to not be too rich but then it was running too lean. He adjusted it some more to get the right mix & now the levels are under the limit! YAY!!! No rebuild necessary!!! After I pay for this, I'm dropping my baby off to get the cat work done (the guy said the rear cat is shot). I'll keep you all posted!

 

I took my truck to the STAR shop to have them do the cat work. The carb guy said the rear cat is shot (you should see how jacked up the O2 sensor was - I brought it home to take a pic of it but seem to have misplaced it) - how would he know that by working on the carb? I'm a novice when it comes to this stuff so I'm sure he's right, I'd just like to know how you determine something like that. He said something like they'd have to drill a hole in the front cat to see if that's any good - I'm hoping they only have to replace the rear cat. I was quoted $95 for the cat test & about $350 for the cat so I'm hoping it's not much more than that. I just want to get my truck smogged so I'm legit - you do NOT want to get pulled over with expired tags, trust me on that!

I'm hoping the STAR guys do great work 'cuz I'm now in need of a new mechanic. My regular mechanic is great but he really didn't want to work on my carb (I was thrilled that the carb guy was able to adjust it instead - that was $100 vs. $375 for my regular guy to do it). It's like my regular mechanic doesn't want to work on my old truck anymore It sucks 'cuz he's really good & very fair in pricing but if he doesn't want my business, I guess I'll have to take it elsewhere. I don't have AC so there's LOTS of room in the engine to do stuff - I've had other mechanics tell me how much easier it is to do stuff since there's so much room - you'd think my mechanic would like that, too.

Thanks again for all the advice, etc. I'm so glad I found this forum - I'm learning so much from everyone & it's awesome to be around people who appreciate good Ford trucks! TGIF!

 

FWIW--we know the carb is running rich. If the O2 sensor is bad, that needs to be replaced. I would fix the carb and the sensor and test again. That cat might be weak, but it isn't dead if I'm reading your results correctly. (It makes a .86 at 25mph, with a .77 max. Clean up the mixture and it might make the test)

 

The carb guy was able to adjust the it to get the #s in the passing level (he showed them to me on the computer after I watched him adjust the carb - it was really cool!) Do you think I need to have it rebuilt yet again? Shouldn't the adjustment do the trick since he got the #s in the passing range? I never understood why the carb had to be rebuilt so often - 3 times in 6 yrs (8/2003, 1/2008 & 9/2009). I qualified for the BAR CAP program in 2008 & 2009 (also in 2005 but they didn't actually rebuild the carb back then) but I no longer qualify & that's why I didn't smog him last year Don't put off tomorrow what you can do today 'cuz it will cost you WAY more in the long run - I learned that the hard way.

I remember my old mechanic saying I'd need a cat sometime down the road (he told me there were 2 & hopefully I'd just need 1 replaced) & even back then he was leery about it & didn't want to work on it but he flat out told me today he couldn't work on it (of course "couldn't" could just mean "won't" ). Considering how bad the exhaust/intake manifold leaks were, I wouldn't be surprised if the cat is shot. He's 27 yrs old (I've had him for 21 of those years!) & I know I've never replaced the cat so that's definitely an old one in him (even if he has just barely over 200K miles).

I was really looking forward to him being smog exempt in 3 yrs but I've recently found out that old law got thrown away so I will still have to smog my truck every 2 yrs as long as I live here. And that's just one of the reason as to why I'm thinking of moving to Montana!

Wish me luck at the STAR shop! Thanks!!!

 

If it passes after the carb adjustment and otherwise runs correctly, run it that way. A new cat is just money out the door.

 

They probably won't get started on my truck till Monday so I can see them again tomorrow to go over some stuff. The plan as it stands is to test the cat ($95) & then replace it if necessary & then certify/smog him. I looked back at my posts from last year regarding my intake/exhaust manifold problem & the 2nd guy I took him to also said I'd need a new cat, which my regular guy had been telling me years prior so when the STAR shop told me the cat was probably bad due to the bad carb dumping so much fuel on it, I wasn't really surprised. I guess I could ask them if they could test him first & see if he passes but I'm worried he'll fail again & then they'll do the cat test, which will show the cat is bad so they'll replace it like originally planned & I'll have an extra $75 charge for the failed original smog test. This whole ordeal has really gotten me frazzled. I know I sound like a broken record & am repeating myself a lot - I just want this to be taken care of by next week so I can be legal once again & then deal with the fines, etc, next month.

 

I dont know where you buy your parts but if you do happen to use AAP for your parts they have real good discounts online to where you can pick up instore or have them shipped to you for free if your order is over so much. Google AAP promo codes, you'll see something like $40 off $110 or other variations. You will see them.

I know they have a big selection of cats for our trucks but I dont know about the brands. Its a thought thou.

 

The engine running rich will cause the cat to overheat and melt inside. When it does that it gets clogged and won't let the exhaust pass through like it should. They probably drilled a hole in the exhaust so they could measure the backpressure in the system. If the cat is clogged, the engine ends up pushing the exhaust through the system and it builds up too much pressure. This hurts engine power and messes the vacuum on the engine up, which causes lots of other problems.

You are going to have to realize you have been targeted by the California smog people. You have a old vehicle, and they do not want you to be driving it anymore, they want you to buy a newer truck. You are finding it harder to get people to work on your truck, and it's getting expensive. Your truck is a old one and it will continue to have problems now and then, it's just the nature of the beast. It may get to the point you can't afford to hire someone anymore, or find someone, to work on your old system, and you might end up getting rid of it. Then they will have won.

See how long you can keep it going, I hope you win the battle.

 

Sorry for the delay in posting the results - the mechanic up the street replaced the cat & my truck is now smog legal & registered up into 2014! He had to do a little more adjusting to the carb but didn't have to replace both cats, just one. My truck's #s are nice & low now The state of CA really doesn't want trucks like mine on the road - the mechanic said it would've been hard to get those kinds of low #s even when my truck was brand new in 1986. I won't have to smog him again till 2015 & I might be in another state by then. If I do need him smogged, at least I now have a great new mechanic to take him to. Thanks for all the advice - you guys are great!!!