PeteyPathy

Got a friends help, he put thumb over vcv idles perfect, take thumb off goes to crap. Went to u-pull it 6 pathys all 90 or newer ? Cleaned MAF when i replaced TPS and CPS it didn't appear dirty or gummed up at all. Update, i couldn't use loaner ride anymore so decided since I know whats wrong with it to go ahead and drive mine. It has decided to run right again all by itself.... Just like it decided to be stupid. Maybe i loosed up whatever was sticking vcv open or something... I don't know!

Looking into the throttle body to the right of injector is a port inside neck of TB reach a stiff piece of wire in there and push the plunger down. Its not vac line it's a primary vac port, allows unmetered air in large quantities. Truck behaves like it has collapsed intake gasket. But it passed the ether test, several times.

No it isn't fuel related.

I know it's not answer you want but I'd buy generic connectors and replace both sides. If you do this remember to cut the harness side back several inches if possible and add in a couple inches new wire to replace the length you loose by clipping old connection out. You don't want to put new connection in and have it come up half inch short of plugging together!

Ahardb0dy was nice enough to get me a working link for FSM. I'm now 90% certain my problem is VCV. Never would have found it without FSM THANK YOU!!!! It's either sticking open or spring is weak. After cleaning with contact cleaning spray it will now idle (barely)

https://www.dropbox.com/s/5zxwrnxnmrni55q/2014-04-05%2010.41.03.jpg Stock 2dr 4x4

Yes vg30i

Haven't seen a sticker. Haven't really thought to look for one either though. I'm interested mainly in vacuum associated with the TB seems to be originating there hard to tell 100% though. The vac lines are all new already i found 1 that was too long and got against belt which cut hole in it, repaired that one. If you can scan vac diagram and maybe TB diagram that would be awesome! I'll PM my email. I'm just hoping against hope that it's not manifold leak. Though that will give me chance to fix couple of things that i couldn't get too cause under intake.

Cleaned all grounds, no change, checked ECU connection and MAF both look good. Found one blick ground disconnected, made new ground to replace it. Update i have now isolated it to a vacuum leak, but seems to be either a solenoid or actuator. With vac gauge on it i can rev way up and slowly back off shows no vac and runs like a$$ till suddenly whistling dies down, vac comes up, if I hold throttle steady at that point (usually around 2500 rpm) then as smooths out rpms come up about 1k and runs right for 10-15 sec until whistling fades back in and runs bad again. It sounds like whistling is coming from throttle body but can't be sure as need someone to keep it running while I search for source. Does anyone have full vac diagram for 87 they can give me please?

Thanks for the suggestion.

Probably a positive i think. I see it all the time at my work. Battery terminal anti corrosive on a small paint brush works well to neutralize this kind of problem. I would be hesitant to scrape it because it is ecu pin if corrosion has weakened it enough pin may break off. Paint it heavily and when you plug it in will transfer to other side of connection eliminating all corrosive

Lol DO NOT use your mouth to suck or blow on that tube ROFL you'll drink some really nasty stuff! A piece of soft wire works well (i use bailing wire coat hanger i had was too stiff to make the bend). You can't actually get to drain from airbox without removing a/c evap core but its always a good idea to clean out blower compartment and front face of evap core you'll be amazed how much better your a/c can work.

Can you give me a rough idea where grounds are supposed to be located? I'll definitely check that. At this point if someone said put 2 aspirin and a cup of coffee in fuel tank i just might try it lmao

Here it goes. I'm desperate for advice guys. 87 2door 4x4 309k!on way to work couple weeks ago stopped at c-store truck ran great. Came out of store truck cranked and died. So what the hell its never done this before? Cranked it and feathered throttle got RPMs worked up (thank god she's a stick shift) limped her to work. It has had a CPS code since I bought it. Pulled codes showing different CPS code and TPS code, tested coil it tested bad, while changing coil found resin on back of ICM melted, that's never good. Replaced TPS ICM and CPS as well as coil. Fired her up started good, died. Can feather throttle and get reved up, once up about about 3k it runs pretty good but no power. So i went to checking vacuum lines found 1 that wasn't secured and had gotten against belt replaced this, otherwise looks like PO had replaced all vac line they are in very good condition. Pulled and checked EGR didn't look so good so i made blocker plate to stop egr flow in case it really was stuck open. When i get it running was putting out very strong gas smell now smells very lean. In process of installing CPS found 2 plug wires that distributor end was almost corroded off, replaced the 3 plug wires on that side and gapped plugs. I had already replaced 3 on other side previously because they were taped together by PO, just hadn't gotten around to doing driverside. I also sprayed through MAF air passage with electric contact cleaner. I noticed that only 1 injector is firing, after a rigged up a way to keep it running while i was under the hood, is this normal? Any help you guys can lend will be greatly appreciated! Peter

Another possibility (my first thought reading original post) is ignition module. It will cause exactly the symptoms you're describing. Don't usually throw a code in my experience but could feasibly be your problem.

Have you considered fuel pressure regulator? If it has failed on high side will over fuel, which accounts for fouling, if #2 is getting way too much fuel even with good spark won't fire right. Here is where my lack of knowledge shows, does fuel supply from pump feed in @ #2 if over pressure as it passes pressure will decrease down the line. Also is #2 the new injector? Possible they accidentally sold you wrong injector? Rx-7 uses higher flow version of same injectors as ours. Just a couple thoughts, i am inclined to over pressure, I'm assuming that when you found crap in fuel rail you removed and thoroughly cleaned ALL fuel lines from tank forward and replaced fuel filter. Blockage in fuel line before regulator would create high pressure infont of blockage normal or low pressure behind. This would account for rich on one side and lean on other.

For system to operate correctly yes, vacuuming system is necessary. Also if you can would be great idea to blow compressed air through system to be sure there are no physical blockages in system. Remove both ends of both hoses and blow through each component individually opposite normal direction of flow. Sometimes when drier fails it allows what looks like little pebbles into system. They will clog condenser and evaporator. Doing this also blows out excessive oil that may be in system. Normally you pull vacuum for 30 mins to an hour to be sure system is completely clear of contamination.

It's not any cheaper here to get a/c work done. You didn't mention having replaced o-rings. If over pressure valve or pop off valve as its somtimes called is where it discharged. See the above post by me where i DIY info regarding a/c drier that is bad causing excessive pressure in system. I'd also check the high pressure switch for proper operation. I'm sorry if pointing out your mistakes offended you. I don't recall saying you should not touch a/c take it to shop. I said there is reason people get certified to do a/c, more to it than squirting a can in it. In my book knowing what i did wrong is first step in learning how to do a job RIGHT. Like adamzan said harbor freight, cheap vacuum pump. Good luck

Gotta disagree Pat, no way 15 is ground it leads to diodes which are NEVER in ground wire. Remember those sensors use very little voltage operate based on resistance. I don't know about this instance but most vehicle sensors use between 3 and 5 volts, max power in ECU is 5 volts. Pins on "bottom" are the outbound and return for the gauges that much is clear, sensors don't generally use ground because where they are attached is automatically a ground. Just need two wires to make an ohm reading circuit.

I'm sorry perhaps you should explain that to the butterfly in my TB under the injectors. "you are not a choke you are an air flow restriction plate :-["

I had similar symptoms on mine when I first got it, after a couple hours of frustration i realized that choke butterfly was partly closed. When i tracked down the wires for automatic choke i found a loose wire at plug. Repaired plug and it and it went back to running normally. Choke is normally closed has to have signal to open so with engine running look down into TB and make sure choke plate is completely vertical.

Second that, it is possible for master cylinder to fail and allow brake fluid to be sucked into intake. Will cause smoke from tail pipe.

Judging by little piece of diagram, 15 is ign power, you don't normally find diodes in ground legs. See how it doesn't go just to speedo but joins line going across top that connects to every sensor? Pin 23 is ground it looks like, for speedo, temp, and fuel. To tell more I'd have to see more complete wiring diagram.

Several issues here. First you opened system without first recovering coolant from it. Second the system was left open several days, this means you MUST replace drier. Third you didn't vacuum system prior to recharging. Forth you didn't replace o-rings on a/c lines. Any of these things will stop system from working properly. As you said there was fluid (green color indicates leak detection dye) on floor you should be able to find where its leaking from. Clogged drier creates too much pressure in lines and can blow them or evap core drier removes water vapor from system. Bad o-ring=leak. When installing new drier it should not be open to atmosphere for more than 5 mins (in very humid deep south where i live) more than that and good chance it will pick up too much water from air causing failure. Filling system from can preloaded with oil/sealant repeatedly over time fills system with liquid instead of freon. It will still cool... Sort of but will not work anywhere close to correctly. Finally there is reason you are supposed to be certified to do a/c work its more than just shoot a can in it for system to work properly.

Experiment FAIL! Back down to 13 mpg on last tank. With consistent higher rpm shifts while staying in powerband.... I really think I've got some kind of intermittent electrical problem. I have noticed a very occasional miss at idle, can't find why... On an 87 DTC code 11 is crank position sensor right? I'm not looking at wrong set of codes am I? Is distributor adjustable on these engines? Maybe I'm a couple degrees off correct timing, that would screw up fuel economy if firing too early or too late.... I'm at a loss guys. Any suggestions are welcome. I've replaced plug wires, reset gap on plugs other than that plugs were good, gap was only off couple thousandths. Haven't replaced cap and rotor because they look ok and were going to have to be ordered in.