Our 78 Tioga FAILED Smog!

We purchased a 1978 Dodge Tioga for $1800 from a "nice" guy on craigslist. We DID NOT have it looked over before we bought because well, we were just plain STUPID and GULLIBLE! The story is long and embarrassing so I won't go there.

The cab and overhead AC and Frig do not work and there's a leak from under the water pump. I've pulled off the wall covering in the bathroom and ceiling because it was coming down but now I don't know what to do with it as some of the paneling came with the paper because of WATER DAMAGE. Now we took it for smog check today and it FAILED@!#$

I'm sick to my stomach about the fact that we were so stupid but not having a frig - no biggy. We'll use a cooler. No AC? It's fall, we'll get one next season. The water pump "should" be an easy fix. The walls? We'll figure something out. But this smog fail is killing me! We can't even use it except for extra house guests.

The test said "Idle Speed HC result: 2210 - Greater that 1400 parts per million"

Where do we start? We changed the oil before we took it in. It was still running a bit rough. Oh man, will we ever be able to use it?

We bought old because we couldn't afford much more. Now look where we are?@! Good thing I still own a tent! LOL!

Oh well, if anyone has any ideas I'd love to hear them. We've ordered a Haynes Repair Manual.
RE: Our 78 Tioga FAILED Smog!

Hello Everyone!
So I see that a few have viewed this post but haven't given any feedback so I thought I'd add a detail that perhaps will illicit a response and thus aid my dear husband and I to a starting point with our old lady.
When we were at the smog testing station the tech asked if there was a "cam" on the engine. I, of course, had no idea what a "cam" is but my husband said he didn't think so.
After we left he tried, with out success, to explain what a "cam" is but he didn't think they could put a cam on an RV engine so it wasn't that. Well, then tonight, after talking with a friend that's a mechanic, he told me that it is possible to put a cam on an RV but that if that was true we probably won't ever get it to pass smog.
Does anyone know about this?
The manual is in the mail so can anyone tell us where to start? Are we going to have to rebuild or replace the engine?
I realize that to many of RV'ers $1800 is a small price to pay for all the years of fun we hope to someday have but we can't afford to dump another $2000 into her. At least not all at once.
Any help would greatly be appreciated.
RE: Our 78 Tioga FAILED Smog!

This is an interesting problem that you have,most things that go along with this is.....cat converter,spark plugs and wires,cap and rotor,clean the jets in your carb..also PVC and air breather.i suggest that you start with a good tune-up and go from there.Also when you changed the oil,yes its good to do but you need to drive it to wear the oil; in a little bit before testing


Senior Member
Re: Our 78 Tioga FAILED Smog!

Hi Susan! Sorry this post has not had many responses, but I assume it is because of the Christmas rush. Despite the condition of your "new" motorhome, I hope after some modifications and repairs are made, you will both be enjoying the RV lifestyle.

There are several "specialists" that frequent our site and hopefully they will provide some helpful feedback. Randy and I are still learning every day and repairs are made much more frequently than we'd like...(ours was bought NEW). Don't get discouraged and maybe try posting again at the top part of the forums. :)


Senior Member
Re: Our 78 Tioga FAILED Smog!

Hello Susan so sorry about your situation. But I feel Chris has the best suggestion and that a 100% tune up is a good start and may eliminate many if not all your problems. You say it want pass the SMOG test, that means it is not running right, either to rich or to lean get a good carburetor machanic repair / rebuild the old one or maybe a new one. BTW by doing all this it will get better gas mileage and run so much better. Good luck

C Nash

Senior Member
Re: Our 78 Tioga FAILED Smog!

Susan, Welcome to the forum. Some previous owner may have installed what we call a high performance cam. If that's the case you will have problems getting it to pass specs. You can install an original cam. Pretty expensive if you have it done. I doubt that is the case but possible as some rvers like to "soup-up" their rv so they can get to the campground faster. :eek: I would do as Chris and Hollis suggested and have a good tech check for the problem. Most of the places that ck for emission are not qualified to diagnos IMO. What state are you in? Sorry we were so long in answering your post but we just saw it today.


Senior Member
Re: Our 78 Tioga FAILED Smog!

Susan, back in the day when I had to get a vehicle to pass a smog test I would do a good tune-up (spark plugs, plug wires, cap, rotor, change the oil and oil filter, air filter) and spray down the carb with plenty of cleaner. Then just before the test I would dump in four or five cans of Heet or STP fuel system cleaner and make sure the engine was up to full operating temperature. All this got every old car I had up in Alaska to pass their emissions test. :eek: :eek: :question:

Post back and let us know how it goes. :) :)
RE: Our 78 Tioga FAILED Smog!

Hi and welcome.I have a 1979 Tioga and here in Spain because of her age i need to take her for a test every 6 months.I have just had her tested and apart from "another" problem that i will be seeking help with,she just passed the emitions.Now this may seem strange but 6 months ago i followed local tradition and had a pressure washer into the exhaust to clear the crap out that gathered in there.This was suggested by friends and my local mechanic,then drove her 15 minutes for the test.I never done this this time and she just made the grade.Not technical i know but it worked!Also stick with the forum as there are some good people with good advice waiting to help,more so with our "Classic" RVs. ;)