93 850NA first time PCV service - failure

[Larva]

Thanks sled driver.

While it may be obvious to some but not to me, injecting smoke into the air intake snorkel...is that with the engine running or not? I'm not a smoker so what do you use to generate the smoke?

The engine starts right up and runs; it just runs rough. I know its something I did because it ran fine before I did the pcv work. I think perhaps the conservative approach is to order a new IM gasket and TB gasket, pull it all apart, check the camshaft and crankcase position sensor wiring and carefully reassemble.

I'm glad I don't have the T5 if there is less room than mine to work in. I can barely get my hand under the IM to remove the oil dipstick bolt and IM support bolt. Sure sign I'm getting older as I'm not as flexible as I used to be!

[erikv11]

Yeah I agree that the TPS guess is not looking so likely. In my case I used a carb cleaner. Vacuum leak is still the first suspect.

For a smoke test you can generate smoke or even use a cigar, do some googling. You do it on a non-running engine, let the smoke waft around and see where/if it escapes. You can also use starting fluid on a running engine, spray it around the intake here and there and if the idle surges then you have a leak.

[Larva]

The car has never had a tune up so I had purchased the tune up kit from FCP that included Bosch plugs, distributor cap, rotor, SP wires, injector seals, serpentine belt and oil, fuel and air filter. I haven't done any of that work yet as I was thinking that if something went wrong, like it has, I would have less new parts to be suspect. So once I get this idle issue straightened out, I will move on to the tune up work. I sure hope that goes smoother than the pcv. I'll get back to the pcv once the new gaskets arrive later this week.

Thanks again for all the interest and recommendations. I'll close the loop later this week, assuming I figure out the problem! If not, I'll be back for more of your kind advice.

[sleddriver]

While it may be obvious to some but not to me, injecting smoke into the air intake snorkel...is that with the engine running or not? I'm not a smoker so what do you use to generate the smoke?

You can also go after it with a home-made smoker using cigars, cigarrettes, incense, fireworks punks, etc. inside of a metal paint can with an aquarium air pump or you can just blow into the sealed can from a tube. These work great on finding vac leaks on our older cars.

No engine running. RSPI has a video on youtube showing his DIY smoker.

You can also use an air-compressor with a second air regulator turned down to 4psi or so. By pressurizing the air intake, you'll hear the air hissing out at the leak if that's indeed your problem.

[Clemens]

Dd you check if the plug wires are on properly after pulling the intake? Also, did you try to let it run for a while cuz the computer might take a bit to reprogram itself after having the battery disconnected. You probably did, but sometimes all of us forget the obvious.

[lcc014]

I did mine (95 855, NA) too back then, no problem at all. However, I did use new Intake Manifold gasket and replaced EGR valve too.

[Clemens]

Also, did you make sure all the rubber o rings stayed on the injectors and they are seated properly? This would be a hard to spot place for a major vacum leak

[Larva]

I did not remove the spark plug wires so I think those are OK. I ran the engine for about 30 minutes yesterday and drove it for a few miles. The miss is consistent across all RPM ranges if that is of any help. I did use a new intake manifold gasket but did not disturb the EGR valve other than to disconnect the exhaust metal pipe below the throttle body so I could remove the IM. Why did you replace the EGR valve, was it malfunctioning? Should I remove the EGR valve and clean it out? When I unplugged the EGR temperature sensor I noticed that the insulation on the wires was less than perfect but I didn't see any bare wires.

The injectors have an O ring where it goes into the fuel rail, and an O ring at the very bottom where it seats against the head and then a larger blue color seal on the head above the lower O ring. All of the injectors, except one stayed in the fuel rail. One dropped out of the rail and I immediately popped it back in the rail. On reassembly I didn't see any missing O rings or seals and they appeared to go back in without a problem.

I do have new spark plugs, wires, distributer cap and rotor but haven't installed those yet. I also have the upper and lower injector O rings that I have not yet installed. I do not have the blue injector seals. As I mentioned before, the car was running fine before I did the PCV work and I didn't want to add more variables by changing ignition parts at the same time. I obviously didn't get something right with the PCV work.

I have ordered a new IM gasket and throttle body gasket and expect them to arrive so I can try again this weekend. When I remove the IM, I'll also remove the EGR and clean it. I did see that I can test it by applying a vacuum to the port and watch for the valve to move.

Thanks to all for the suggestions and tips. Hopefully with your help I can get the problem identified and corrected.

[lcc014]

I replaced EGR valve because the old (original) one was not holding vacuum. Also, there is a hole from throttle body into EGR valve. Most people found that that was plugged, mine was too. I cleaned the small hole up while Intake Manifold was out. I also replaced injectors O-rings too since they were from original.