It Failed

[azshtr]

I've read the other posts regarding failed emissions but thought I'd ask. The jeep failed the HC and CO badly. The little booklet they give you indicates either Ignition, Catalytic converter, or Vacuum leaks. I've done a TFI upgrade so probably rule that out. ( I'll recheck the timing though). So I thought vacuum line replacment for sure, maybe rebuild the carb, and check the air control valve. Replace the PCV valve for good measure. The engine has 103,000 miles so I don't think it should need a cat... should it? Any thoughts? I have a free retest coming and hope to get it through without a waiver or major bucks.

Thanks

360 with 2150 carb. All stock.

It does seem to idle a tad rough, but runs good at speed.

[AMX factor]

You need a cat. A new cat will probably solve 80% of your problems. Rebuild carb, run it a bit lean and a bit high on the idle, run Premium gas and add a gallon of denatured alcohol, new plugs, wires, oil change, get the engine good and hot before gettign the test. Make sure no vac leaks also.

[azshtr]

Could you recommend a brand name for the rebuild kit? I can get a JP Sorenson kit for $22. Is that as good as any? The Cat original equipment is $129 but the universal is $79. ( By the way does the stock one have an tube going to it, that was one of the questions. I havn't looked at it yet) I don't want to cut any corners if I shouldn't regarding quality / cost. Is the universal generally acceptable? Its a clamp on. I assume the original equipment is weld on, the sales lady on the phone didn't know. I can weld but I'd probably let a shop do that.

[SBJeep]

Mine has failed before due to a blown power valve. It failed at idle, but passed at 2500 rpm. This would also cause it to idle rough like you say. Even when everything is fine, mine needs to leaned out at idle to pass.

[azshtr]

Is there a difference in carb rebuild kit quality. Autozone has a Sorenson for $22, Napa has their own brand for $55 and PepBoys has Borg Warner for $55. Interesting that both of the higher priced kits wanted a number off the carb but Autozone didn't. Is it worth rebuilding or should I just put on an Edlebrock? I'm not after that much more in the way of HP just a good driving vehicle.

[Chevelleguy]

The 2150 uses a Holley 2 stage power valve and the only quick way to get one is with a kit. I also would recomend the converter but if you know someone or a shop the has one of those Rayteck infared temp guns, they can check the cat for you very quickly. With engine fully warmed up, check the inlet and outlet temp. Should be hotter coming out by at least 20 deg. if not more for the older cats. If same temp or colder, cat is bad. The conversion process creates heat.

[tgreese]

Originally posted by chevelleguy:
The 2150 uses a Holley 2 stage power valve and the only quick way to get one is with a kit. I also would recomend the converter but if you know someone or a shop the has one of those Rayteck infared temp guns, they can check the cat for you very quickly. With engine fully warmed up, check the inlet and outlet temp. Should be hotter coming out by at least 20 deg. if not more for the older cats. If same temp or colder, cat is bad. The conversion process creates heat.Nice - I hadn't thought that there has to be a temp change. Interesting, a good test. You could probably do it at home with DVM and a thermocouple. Check the Omega catalog.

NAPA online lists the 2-stage power valves separate from the kits, but I haven't tried to buy one.

best regards :cool: Tim

[ September 14, 2003, 07:24 AM: Message edited by: tgreese ]

[azshtr]

This may be a dumb question but what is the power valve? I'm looking at an exploded view diagram and don't see one. Is it also known by another name?

[Chevelleguy]

In the bottom of the carb under the accelerator pump. Screws into carb, then has a cover with four screws.

[azshtr]

Originally posted by chevelleguy:
In the bottom of the carb under the accelerator pump. Screws into carb, then has a cover with four screws.I see it. Its called the economizer valve on my diagram. If I have to remove the carb to do that I may as well rebuild it. It would laso be easier to do all the vacuum lines with some of the stuff off the engine as well. Oh well, I'm glad this isn't the daily driver... it might take a while. I think I'll try and pass after the carb, vacuum line, timing checks. If I still fail its cat time.

Thanks for the help.

Thanks for the help.