Anyone know what would cause a Hard start when jeeps hot.

 

Look up heat soak, dont know if its possible in the renix though, always see it on the newer xj's. Have you visually checked the cat and made sure its there and functioning. When I bought mine it had no cat, I didn't notice because of the awesome skid plate. Failed miserably like you. Replaced it and did alot better but still failed. Turned out to be a bad O2 sensor. Go to a different inspection site if you can, you DO NOT have an obd system of any kind so I dont know how you failed that. The oil on the filter is called blow bye. Its caused by blockage of the two vacuum lines coming out of the valve cover, ensure there is no blockage especially the rear one. Also look up cruisers renix tips. Check the tps adjustment, the instructions are in his tips.

 

How do I check more on the cat? It's shiney with a bar code tag on it so I'm guessing new ,the mufflers the same.Also I asked what OBD was he said that my check engine light wasn't working.

 

Radiators new,a new water pump and it flows through the egg shell really nice. So I'm leaning towards my sensors being bad.

 

Couple things 87xj2. First you are in a high pollution zip code your test for those types of areas. No where else do they test like that but here. A normal test the engine revs to about2500 rpm for about a minute then returns to idle. This is normally where it fails. Your test is that part and a run test just as if you were driving it. The problem is under load the old engine makes a lot of pollutants and the limits are very low. You are not likely to get it to pass without a rebuild. They are doing this specifically to get rid of these cars. Second it is the responsibility of the seller to certify the smog, don't know if you can run him down but the state will back you up. One other option is to register it in a zip code that is lesser test. Bummer I've been on that road. Where are you?

 

Wow only thing I can think of if the cleaning an checking everything doesn't work is rebuilding one of the motors I got sitting. I live in Menifee

 

As far as I know, there is no Check Engine Light on an '87 MJ (or XJ). The seller is responsible for performing the smog certification but it's the buyer's responsibility to register that vehicle within 90 days of the test. Replacing your O2 sensor and MAP will help. Fixing your manifold leak will help. Check for any vacuum leaks. High engine temps will cause a lean condition and elevated NO levels, vacuum leaks (especially to the MAP sensor) will result in a rich condition that elevates the CO numbers. It sounds like you've got a variety of these things, along with some other possible issues.

When, exactly, did the PO have the test performed? How many miles has it been driven since then (the mileage should be on the original test results)?

 

You should also check the tube to the map sensor is not blocked. My 88 MJ had that problem when I first got it running. I'm surprised that mine passed Cali emissions the day after I got it running after replacing the head.

 

Pull a spark plug and post up a photo. I'd replace plugs, wires, cap and rotor.

If it were mine, I'd be doing all the ground refreshing as poor grounds can screw with the signals the sensors send to the ECU.

 

Good advice. I would start by performing an external overhaul. Replace your MAP and O2, replace all soft vacuum lines and confirm the integrity of the hard lines, refresh your grounds and C101 connector, clean the throttle body (pretty sure you said you did that), test and adjust the TPS (see the pink link in Cruiser's signature above), replace your plugs, wires, cap, rotor, PCV and air filter along with an oil change. The oil on your air filter is probably the result of a faulty PCV valve. Confirm that you have no leaks in either your exhaust or intake manifold, replace the temperature sender and maybe run a can of that 44 stuff (Cruiser54, a little help?) through the tank for good measure. The parts will likely cost less than $300 and while some of that stuff may not need to be replaced, knowing that it has will give you peace of mind moving forward with a new-to-you truck.

If it passed smog recently then it's unlikely to be something major.

Can someone confirm, does an '87 MJ have a Check Engine light? I thought those were part of OBDII.

 

BG 44K is amazing, and there is no CEL on any REnix.

Agree with your plan of attack.

 

Sorry guys, was posting last night on my mobile. It took me 30 min to post that. In any case what i was trying to get to is that if you can't pass a visual then the actual test is irrelevant. You mentioned a new CAT, it has to be the proper one for your year and model as state by the CARB you can look it up on line for the number and match it to yours. Even if it is new and the wrong number it will fail on a visual. Also any OBD items amiss will fail, you don't have any of those to be concerned about but if the guy testing thinks you do then it's a problem cause he is looking for them to be there. Also anything that is not correct regarding exhaust, intake, emissions, etc is a cause for visual failure including a rough idle. (fluctuating tach) Anything that is cracked, leaking or missing is an opportunity for failure. I have two xjs with 250k both from high pollution zone that couldn't be tested, I suspect it is the run test which puts more load on the engine and increases blow by. I also agree with the other all is great advise, especially cleaning or replacing the vacuum lines.
Bird

 

So refresh all my grounds before I replace sensors because bad ground can screw them up.clean everything that you guys listed.then check everything. My blowbye pipe on top is shot so can I make one out of metal or somthing? Also the smog papers he gave me were for a different truck I had to take a second look at it. It's all good though couldn't pass up a 500$ Mj I drove home. Will post pics later on. And link of a before and after. I'll take pics of everything

 

The tubes dont do anything special so you can fab your own if you want. You need to make sure the grommet in the valve cover is in good shape also, its common for them to close up on the under side of the valve cover.

 

Move out of the communist state of california. Or continue to have your rights abused by the liberals who run the state.