rich_e777 Posted October 31, 2013 Author Report Share Posted October 31, 2013 I call it a vacuum spider, I am sure that's not its official name. But its the hard plastic vacuum lines that are under the intake plenum. They commonly break anytime you are doing any repairs around the throttle body, or under the plenum. Sometimes you can get lucky and just use rubber vacuum hose to repair it. While you are under there, check the PCV Valve, and hose. The hose is a known problem to break when you do any repair under the plenum. It can also be a royal pain in the ass to get back together correctly. This is a 3100, no such lines exist under the plenum and the PCV runs from the front valve cover, enters the plenum just aft of the TB then moves on to connect on a piece with the coil packs. All that is under my plenum is the fuel rails and harness associated with it, and a metal coolant line that is bolted to the LIM and is connected near the water pump. I have it off and there is evidence of fuel inside the plenum mixed with what appears to be oil. Have the fuel rail assembly with me and will test the injectors after I eat. Quote Link to comment Share on other sites More sharing options...
l67ss Posted October 31, 2013 Report Share Posted October 31, 2013 Make sure to use new injector o-rings before reinstallation, i learned the hard way This is a 3100, no such lines exist under the plenum and the PCV runs from the front valve cover, enters the plenum just aft of the TB then moves on to connect on a piece with the coil packs. All that is under my plenum is the fuel rails and harness associated with it, and a metal coolant line that is bolted to the LIM and is connected near the water pump. I have it off and there is evidence of fuel inside the plenum mixed with what appears to be oil. Have the fuel rail assembly with me and will test the injectors after I eat. Quote Link to comment Share on other sites More sharing options...
Schurkey Posted October 31, 2013 Report Share Posted October 31, 2013 As for the converter I`m only going to bolt it up to pass the few remaining tests over the next few years and I don't want to wear it out unnecessarily. If the engine is running right, you WON'T wear it out for 100,000+ miles. The OEM cats were under warranty for 50K or 5 years, and typically lasted much longer. If that turns out to be what the current issue is, if its not it will stay were it is until the time comes I can legally remove it so I wont have to worry about it getting clogged up. You CANNOT EVER "legally" remove it and still drive it on the street. Disabling a cat is a FEDERAL offense--has nothing to do with state emissions inspections. You stand a pretty fair chance of not getting caught and not paying the penalty; which isn'tt the same as legal "permission" to remove the thing. Just confirmed the cat converter is shot, rattling pretty bad. So that's one thing, but I thought one should be able to get a lot of miles out of them, only put a few thousand on it as it hasn't always been my DD. Also curious as to any conditions that would make them where out faster. The converter may be busted-up inside due to road impact; or it may be busted-up inside due to OVERHEATING FROM EXCESS HC EMISSIONS entering the catalyst structure. My money is on the engine having excessively high HC emissions, which destroyed the cat--in that order. FIX THE ENGINE FIRST. THEN, put on the new cat. Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted October 31, 2013 Author Report Share Posted October 31, 2013 My money is on the engine having excessively high HC emissions, which destroyed the cat--in that order. FIX THE ENGINE FIRST. THEN, put on the new cat. As is just about everyone else's cash too. Having fuel in the plenum doesn't seem right to me, so what would suck fuel vapors to the top of the engine over the injectors? (A question i`m currently figuring out[PCV is pulling excessive fuel vapors existing in engine?]) The most evidence being around the EGR molding in the plenum itself just behind the throttle body. Still looking for that "vacuum spider" I think some of you are messing with me on that one. Should have pushed harder for that leak down test when everything was apart but the owner of the garage didn't agree with the logic behind it so what could I say wasn't my shop. That hiss from the UIM has me thinking its a valve not seating all the way, don't know what else it could be and have to assume that's what they sound like as I`ve never heard a defective valve before. Do these plenums have a weird airflow effect inside them that could cause it? Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted October 31, 2013 Author Report Share Posted October 31, 2013 (edited) Fuel injector resistance is 12.5 for 4 of them and 12.6 for the middle two. Is there any way to test the fuel pressure regulator while I have the assembly with me or do I need to? Would it help the injectors to submerge just the tips in injector cleaner if build up is suspected of fouling the atomization process? I do not see any build up in them but on two of the injectors the area around the tiny holes is darker than the other four. Edited October 31, 2013 by rich_e777 Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted October 31, 2013 Author Report Share Posted October 31, 2013 Damn, got rained out before I could get at a gauge to check compression. If its the piston rings then the cam shaft, rods and piston etc all have to come out don't they? Both of my manuals are in the car down the road in storage. Quote Link to comment Share on other sites More sharing options...
l67ss Posted October 31, 2013 Report Share Posted October 31, 2013 Just the topend pan rods and pistons. Cam and lifters etc can stay in place if no damage to them. Damn, got rained out before I could get at a gauge to check compression. If its the piston rings then the cam shaft, rods and piston etc all have to come out don't they? Both of my manuals are in the car down the road in storage. Quote Link to comment Share on other sites More sharing options...
Schurkey Posted October 31, 2013 Report Share Posted October 31, 2013 I'd consider looking at the fuel tank vent, including the evaporative emissions canister and it's purge valve. GM had a lot of problems (many!) years ago with defective purge valves; the canister got soaked in liquid fuel, then the liquid fuel was "purged" into the engine via manifold vacuum intended to draw fresh air through the canister. I'm thinking the canister is cleverly hidden in the left rear fender, with a mile-long vacuum hose connecting it to the engine. Maybe yours is different. Quote Link to comment Share on other sites More sharing options...
l67ss Posted October 31, 2013 Report Share Posted October 31, 2013 <memphis warrior used to go pirate raids to the upullit on watkinz Alright will be pulling of the plenum and testing the injectors a little later I can test resistance(Ohms), might as well pull the IAC sensor of the TB and the EGR clean it up to couldn't hurt. This "vacuum spider" that's the first time I`ve heard that term and have no clue what that is. I wish I could remember what the CO and CO2 numbers were before my last test, but the CO now is 1.06 and the state limit is 1.2, and the CO2 is 12.7 but TN doesn't care about such things. Also could it be that I have to put it through some drive cycle after having the battery, plugs and a few sensors disconnected? If I have to get another converter Its only going to be on the car to pass the test and its coming right back off. Road trip to AK sounds good but with my suspension in its current shape I don't want to push it. It would be about a 10 hour round trip on expired tags, no insurance, and I don't think I have enough ammo to fight my way through Memphis twice, once maybe. Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted October 31, 2013 Author Report Share Posted October 31, 2013 I'd consider looking at the fuel tank vent, including the evaporative emissions canister and it's purge valve. GM had a lot of problems (many!) years ago with defective purge valves; the canister got soaked in liquid fuel, then the liquid fuel was "purged" into the engine via manifold vacuum intended to draw fresh air through the canister. I'm thinking the canister is cleverly hidden in the left rear fender, with a mile-long vacuum hose connecting it to the engine. Maybe yours is different. Correct, I know right where that is, changed some rotten lines on it a few months ago. Did they change the design in later GMs that would be compatible with mine if defective? Now I want to go back to my car with a maglight and check it out but TN has some thunderstorms right now and cold, dark and wet isn't appealing right now. maybe if it were just two of those I could suck it up. Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted October 31, 2013 Author Report Share Posted October 31, 2013 <memphis warrior used to go pirate raids to the upullit on watkinz I bet they have some sweet older stuff turn up over there with just a blown LIM or head gasket. Quote Link to comment Share on other sites More sharing options...
l67ss Posted October 31, 2013 Report Share Posted October 31, 2013 Thats where i got my supercharger, 5k miles on it gave $75 car had some busted pistons I bet they have some sweet older stuff turn up over there with just a blown LIM or head gasket. Quote Link to comment Share on other sites More sharing options...
Schurkey Posted October 31, 2013 Report Share Posted October 31, 2013 Did they change the design in later GMs that would be compatible with mine if defective? No idea. The defective canisters I dealt with in the '80's would be full of gasoline, heavy as hell. If yours isn't...may not be defective, and therefore not the problem. I mention the canister because it's a way for fuel to get to the engine without being squirted-in by the injector. Another possibility is ruptured diaphragm on the fuel pressure regulator. Can't remember if you've checked that or not. Quote Link to comment Share on other sites More sharing options...
AL Posted November 1, 2013 Report Share Posted November 1, 2013 I am thinking fuel pressure regulator as well Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted November 1, 2013 Author Report Share Posted November 1, 2013 Got a gauge and tested the fuel pressure, seemed to read about 39 to 38psi at "ON" and dropped about 4 to 5psi at start up to idle, not far from the specs. Ended up getting a new regulator for a good discount as the AZ was clearing out old items in there over head to make room for new items. For good measure I thought to get this http://www.autozone.com/autozone/parts/1994-Oldsmobile-Cutlass-Supreme/Canister-Purge-Valve-Solenoid/_/N-j1579Z9ixxi but cannot locate where it would go. It looks as if it might connect to the canister in the drivers side rear fender canister but that electrical connection eludes me as to what it is. Do not see one on that canister or a way to even remove it, the frame and unibody are in the way. My dealer manual doesn't cover either of these two components, nor the fuel rails, injectors, regulator or harness at all. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted November 1, 2013 Report Share Posted November 1, 2013 purge solenoid is on the back of the engine, right next to the MAP sensor, IIRC. nearly impossible to pull out with the ICM/coilpacks installed. Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted November 2, 2013 Author Report Share Posted November 2, 2013 That thing that hangs on the Coil bracket I bet. just tracked it down in the manual`s wiring diagram, of course the index does not mention the page number or section in this huge thing. Also was able to loosen that canister in the rear to lift it and it seems light and empty, good thing I guess because I see no way to get the thing out if it were defective. Will be a few more days before I can get a compression test gauge but hopefully its not the piston rings, not loosing oil, no smoke coming from exhaust and same to have the right amount of power for a 20 year old 1st gen 3100 that has been taken care of to the best of my abilities. Thanks for all the replies dudes. Quote Link to comment Share on other sites More sharing options...
Pontiac6KSTEAWD Posted November 3, 2013 Report Share Posted November 3, 2013 No vacuum? I will be the first to admit that I don't know the 3x00 engines like I do the 3.1/2.8 engines. But I looked at my 3100 in my neighbors 94 1.5OBD Corsica, and it has a vacuum line that goes under the intake plenum that goes to, as far as I can tell, the fuel pressure regulator. Did they change the TB, and vacuum emission control systems on the 94 W? Sorry for the long response, I usually only have time to get on 1-2 times a week. Quote Link to comment Share on other sites More sharing options...
Pontiac6KSTEAWD Posted November 3, 2013 Report Share Posted November 3, 2013 And according to this link.. http://econtent.autozone.com:24991/znetrgs/repair_guide_content/en_us/images//0900c152/80/21/7d/3a//large/0900c15280217d3a.gif There is a vacuum system.. Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted November 14, 2013 Author Report Share Posted November 14, 2013 That vacuum line from the MAP sensor to the regulator runs over the plenum, other than the fuel rails and associated harness there is only a coolant line. Attempting a vacuum smoke test using a cigar, saw it on a youtube video and figured it was worth a try. Cannot see any smoke coming out of anywhere other than the hole in the rubber intake duct where the rear valve cover pipe goes so I think I`m doing it wrong. Also thinking I might need more smoke or pressure than my lungs can produce. I do have a fog machine and lots of fog juice. Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted December 4, 2013 Author Report Share Posted December 4, 2013 Its done, Figured it out, was not the Converter, could not have been converter. Get $80 refund taking the new one back and learned how to weld exhaust componets:dance: Got access to grandparents garage again with proper equipment(no field repairs here) and got the converter off It was exactly like the new one inside but darker, whatever I heard rattling around about a week ago was gone, sounded like a few pieces of gravel before and I`m not hard of hearing. Consensus of the shop was that since the converter had less than 5,000 miles, had all ports clear and unclogged, and had no debris floating around that it was still good and I should re-install it. Done. Between my last test(in Metro Davidson County) and today(Wilson County) the only thing that was changed was a new battery, a thicker front PCV hose(other one was to thin and made a noise similar to lifter tick) and new transmission cooler hoses. Well and removed and reinstalled current converter. It went from a HC reading from Davidson county of 602 to a Wilson CO. reading of 74!!!??? So it seems repairs are over, fucking finally. GOOD GOD is that coolant leaking!!!!!!!!!!!!!!!!!!!!!!!!!!!!! no, no just water. Heart palpitations. Quote Link to comment Share on other sites More sharing options...
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