legacycentral bbs

Ok, so I have an EJ20G in my '91 SS the engine is rated at around 220bhp. I am sure some of you have seen my other posts, I am having problems with my fuel injection.

The injectors in the car right now are around 480cc. They are yellow side feeds, I dont really know what they came off because they were in the car when I bought it.

So just the other day I started wiring up my hks super afr because the car was running way to rich on those injectors and I wanted to turn them down to make the car driveable. (This is where the problems start occuring) I get the afr wired up, and when I try to start the car it wont start ( I later figure out that the remote wire attatched to the starter wasn't making a good connection) But for some reason the injectors but have been tripped and turned on long enough to fill up the whole intake manifold with gas so that it starts leaking out of the PCV nipple underneath the throttle body.
So I unhook all the afr wiring (which is a total of like 5 wires) and leave it for the night.

I let it drain and come back the next day, I try starting it and it is hard to start but eventually does. And when it does the rpms climb all the way up to 4k before I shut the engine off. I have an A/F gauge and it is reading very very lean. The red LED's are all the way to the lean side.

So here I am, wondering what the F is going on, I checked and there aren't any wires that could have been crossed or damaged when I tried installing the afr. I don't understand how it could go from super rich to super lean without me changing anything.

I tried resetting the ECU and nothing happened. I am wondering if the O2 sensor could be fouled or not reading right.
Would the O2 not seeing enough oxygen make the injectors lean it out that much? Why does the rpm climb like it does? This is a new problem, before it just ran bad because it was rich.

Is it a wideband O2?

No, its just an autometer gauge

If it's not a wideband O2 sensor then you are not going to get accurate readings from your gauge.

Well I know its not the most accurate, but in cases like this it is atleast there to warn me. I know it is running lean because before it was just above stoich.

I know that in my experience, it was completely not accurate. I didn't give me any indication of what was acutally happening. It just bounced around a lot and sometimes stayed around par.

Ok well we can stop arguing about it, but I still have a problem with my car idling past 3 grand for no reason

let the car warm up, i had a hks afr there crap. it worked for a while then i blew a piston. then when i tried to make it work agian i had the same problem as you, check all your wires agian just to be safe, when i hooked my hks back up it stalled ran way to rich and was all messed up, sell the hks or bring it back.

damn. Well it isnt even hooked up right now and it still does the 4grand idle. Are you sure it wasnt a user problem that caused your engine trouble nico?

Well I found out the answer if anyone cares. There were 3 things. First, since its a different engine, there was a PCV line not attatched to anything so I have to plug it because it was letting un-metered air in.

Second, there was gunk in the throttle body keeping it from closing all the way.

Third: The throttle linkage was sticking along with the cable. I cleaned the cable and the linkage, now it runs like it did before, crappy rich.

Here is my two cents on the rich running. If the o2 sensor is not working the ecu could be seeing a low voltage (lean) and opening the injectors longer. If the MAF is not working properly the ecu could be getting a signal that indicates lots of air thus trying to compensate by keeping the injectors open longer or decreasing the IAC opening, I had this happen when a feather was stuck to the screen in front of the MAF sensor, creating a vortex at the sensor. Do you have the scan tool program to monitor the sensors? I am willing to bet that the O2 sensor could be out from running rich for a long period of time. Try running it with out the O2 sensor not plugged in to see if there is a change in operation indicating that it still works. Also clean you MAF with break cleaner. Check your IAC for continuity I believe it is supposed to 9-12 ohms. Hope this helps!!!

Well for the most part I think I solved the problem, I am still waiting to get the proper fuel lines for my smaller injectors. Once I get those put in it should drive relatively normal.

I am betting the o2 sensor is probably going to die pretty soon because its been driven for so long running so rich.

I'll check the MAF just in case. But as of now it just acts like a car running too rich.