Car is not any better. 1 step forward/backward. Advice.

[MyDodgeDip]

I’m going to disagree with MyDodgeDip on the catalytic converter, if it’s starting to plug up the exhaust is restricted and again the engine can not breathe its normal amount of air.

Actually, you're agreeing.

And again, unless the cat is clogged it's not the problem here.

Most plugged cats will bog the car down like K_CAR_WAGON said. Even if partially clogged, you would have hissing out of the manifold to exhaust joint with any sort of revving up. Generally they get worse as they warm up and then stay bad. If this is an intermittent issue and if he can get it up to 70 or 80, I think it's ok.

Butch, thanks for the extra info! Guy, like Butch said, check the fuel injector spray pattern. See if you're getting a dribble/dump kind of thing or a good even spray. The filter should not have any fuel soaked into it. Maybe a smell of it from the vapor after you turn the car off, but not wet. If you have a spare MAP sensor, try it, it's easy to swap out.

Did you guys pull the plugs when you worked on it? Like the others said, they could be pretty fouled up.

As for the valve cover, spring for the 20-30 dollar one piece unit with the metal side pieces. It's worth every penny. Dipstick tubes sometimes rust out and sometimes just leak. If yours is not rusty you can probably just re-seal it with some RTV for the time being.

[Pete in NH]

I agree on the one piece valve cover gasket, i put one on the 86 reliant this summer. So much easier and less messy than dealing with RTV. worth every penny and its as dry as a bone. Guy I had replied to one of your earlier posts on valve cover gaskets, take a look down the list.

My experience with a bad catalytic converter on my 84 Aries was quite a trip. It would run okay then a chunk of honeycomb material would move to a strategic place and plug things up and the thing would run awful. Then you would hit a bump in the road and it would run okay

[89ARIES]

Hi Folks. I may be getting some of those cat symptoms. There has been developing a pattern. Idles better when cold, but engine is sluggish and hesitant while driving. Once warmed up, most of the power
is restored, but it is bucking and attempting to cut out. Happened a LOT today. Also, computer is no longer throwing codes, except 12,55. I am hoping it stays that way since then we can rule out electrical problems, right?

[89ARIES]

I called the family mechanic this morning. He said he never replaced the fuel pump or catalytic converter. He also said he obtained the trottle body from the junkyard, dissassembled it first, then put it back together. Butch, the scanner basically prooves the TB is functionally properly, right? I really appreciate all the input folks. It makes me feel better as knowledge is power. Now, if I can just put all the suggestions
into a ranked order checklist from cheap to most expensive and what to try first. I guess check the fuel spray, right? The air filter was wet with gas, but not terribly dirty. When the gas sprays, it looks
like a gurgling pond of water. Is there a way to test the fuel injector to see that its good?

[89ARIES]

Oh, the fuel is a dribble, dump type of thing.

[K-CAR_WAGON]

If your car is still coming up with code 12 after 15 ignition on/off cycles you probably still have an intermittent electrical problem (intermittent loss of power or ground to computer - bad connection, power spike of computer or a bad computer or voltage to computer dropping low due to a bad battery, a high resistance connection, or something amiss in the charging system or high current draw by the starter or an intermittent short somewhere). I think code 12 should have cleared out by now.

Since Butch reworked part of the wiring harness (fixing some of your other problems) has code 12 ever disappeared? How many power cycles? Do you have a hand held code scanner with a long cable. It would be useful to find out when the code 12 first reappears after clearing out. (To try to correlate to to something.)


Butch's scanner test does not prove everything related the throttle body is fine. Read his previous comments:

Butch wrote:
"Car has 20 inch of vac at idle, vac isn't a problem. Fuel related problem makes more sense since the dead O2 was black. Next step, check plug condition, tap in fuel pres gauge, check injectors spray pattern. "

He also suggested trying to replace the MAP sensor that you got in the junkyard.

Since he has looked at car (and is an expert) I would suggest you follow his suggestions.

As to whether the cat is clogged. A mechanic can measure back pressure or can try disconnecting the exhaust prior to the cat input as a test to see how the car reacts. However, with most clogged cats the engine appears to get noisier, and the car will generally run poorer and struggle after it warms up, and your top speed tends to get limited (maybe to 50 mph). If it gets really clogged you may notice a very weak exhaust stream out the tailpipe. If you see a few cars with clogged cats you get a feel for it.

You need somone with experience to look at the spray pattern from the injector.

[89ARIES]

Oh s"'t, that means there is still an electrical problem. Is that 15 times you turn the car on, or just 15 times you turn the key?

[89ARIES]

I guess this means its time to replace the entire engine wiring harness.

[K-CAR_WAGON]

15 on/off cycles. Don't jump to conclusions that you need a whole new wiring harness replaced. I have had this code show up regularly on one car with its battery on the way out and on another car with bad connections at the battery terminals. You really need to know when the computer is resetting for starters. You need more electrical troubleshooting. If its just reseting when you start the car and draw alot of current through the starter but not resetting during normal running operation it might not a big issue.

http://minimopar.knizefamily.net/fault/code12.html

Your poor idling issue may be a fuel issue totally unrelated to the problem of the computer resetting.

[89ARIES]

Well, the battery connection may be questionnable as a friend and I removed what looked like a partly connecting and rusty band of exposed wire ends. We reattached it after
a cleaning, but it probably isn't quite flush cause the thigamobobitt metal circle thing is too large.