Rollie715 Posted April 25, 2006 Share Posted April 25, 2006 OK, Here's my puzzle. Components: Low mileage EA82 Motor from Japan, SPFI, everything stock New plugs, rotor, wires, cap, gaskets, filters, belts. Symptoms: Fuel runs too rich at mid rpm range 2500-3500 Low rpm seems ok Motor seems to flood out when given full throttle at mid range. When accelerating, it has more power at 1/2 throttle then full Fuel injector seems to be pumping too much gas. Occasionally it will almost die from richness and emits black smoke out the exhaust. What I've done so far: Replaced throttle body-fuel injector twice with other known good ones. Includes all the electrical devices attached to intake system, throttle postion sensor, air flow sensors etc. Replaced plastic/rubber intake ducting, all clear and firm. Checked intake route into air filter, all clear. Blowned out all fuel lines back to the tank. Checked timing belt, timing is correct. Checked cylinder compression, all are good. Replaced electric fuel pump with known good one. Ignition timing set correctly. Checked inside of catalytic converter, no restrictions. Still exactly the same problem, nothing I did made a difference. Things I haven't done yet: Check muffler for restrictions or clogging Check or replace sensor on Cat, What effect does it have? Replace Computer, Why would it be the problem? At this point I'm open to any suggestions you might have. I'm even williing to try something that doesn't make sense. Any Suggestions? Thanks Rollie Quote Link to comment Share on other sites More sharing options...
bgd73 Posted April 25, 2006 Share Posted April 25, 2006 You have pretty much said it all from what I can see. Is fuel at 21psi? A pump too low or high can do strange things to OEM regulator. Quote Link to comment Share on other sites More sharing options...
robm Posted April 25, 2006 Share Posted April 25, 2006 The Oxygen sensor on the cat controls the mixture. This could be the problem. If you have replaced everything else, try a new O2 sensor. Could try resetting the computer. I can't remember the sequence, do a search. Good luck. Quote Link to comment Share on other sites More sharing options...
Meeky Moose Posted April 25, 2006 Share Posted April 25, 2006 coolant temperature sensor.. it tells teh ecm what temp the engine is.. if its reading 20 degrees when the engine is 185 or so, its gonna flood out.. think i got one thats flaky on my spfi wagon.. Quote Link to comment Share on other sites More sharing options...
robm Posted April 25, 2006 Share Posted April 25, 2006 Yep, CTS will do it too. I thought you tried it already, but a closer read of you post show you haven't looked at it yet. Apparently , the connector gets corroded. Try cleaning it. Lots of posts on here about this device. Good luck. Quote Link to comment Share on other sites More sharing options...
torxxx Posted April 26, 2006 Share Posted April 26, 2006 The Oxygen sensor on the cat controls the mixture. This could be the problem. If you have replaced everything else, try a new O2 sensor. I disagree. I've ran many SPFI and MPFI cars with the O2 sensors unplugged. the CEL doesnt even come on..... Quote Link to comment Share on other sites More sharing options...
Qman Posted April 26, 2006 Share Posted April 26, 2006 Without the O2 sensor these computer controlled engines have no reference to go by for fuel control. When they are unplugged or nonfunctional they go fat causing poor mileage and a number of other problems. That's why they are there! Temp sensors are the biggest cause of drivability problems of all. Idle, cruise and WOT issues can be attributed to a bad temp sensor. A code check should reveal these issues. Quote Link to comment Share on other sites More sharing options...
robm Posted April 26, 2006 Share Posted April 26, 2006 He didn't mention a CEL, so that is why I suspect the O2 sensor, since they are famous flor crapping out without setting one. The car will run, just not efficiently. The car won't set any MPG records, that is for sure. Quote Link to comment Share on other sites More sharing options...
Rollie715 Posted April 26, 2006 Author Share Posted April 26, 2006 Thanks guys, for your comments. I'm trying to track down a good used O2 sensor for cheap or free and then I will try it to see what happens. It is a one-wire device. I'm also looking for a computer to try. It's an 88 GL Wagon 4x4 built in 12/87 Computer says: 22611 AA392 MECF-022 4E 42 Meanwhile I just keep driving. Fuel mileage has been hovering around 20mpg after adjusting the odometer reading for running 27" Swampers. Rollie Quote Link to comment Share on other sites More sharing options...
jeffast Posted April 27, 2006 Share Posted April 27, 2006 i second the o2 sensor replace it is like 20 and it plays a big part in the mixture Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted April 27, 2006 Share Posted April 27, 2006 20 MPG with 27" tires is about normal. Sorry dude. My wagon - same engine, same carb went from 32 MPG with 175's and 2WD 5 spd with 3.7 diff, to 20-22 MPG with 215/75R15's (28") and 4WD with 3.9 diffs. Swampers are wider than my MT's, and being bias-ply your mileage will be teh suck. GD Quote Link to comment Share on other sites More sharing options...
manxsta Posted April 27, 2006 Share Posted April 27, 2006 If your coolant temp sensor is working fine and actuallly functioning..you will notice idle up at cold start..after engine is warm..it will drop to normal idle..if it is hoovering above normal idle..that will be the problem.....i run a few ea82t,s and the oxygen sensor does not make the cel come on..if you disconnect it.... and will not let black smoke belch out the rear when disconnected..diesel will do this though..lol:lol: so i would look elsewhere for the problem.....cheers Quote Link to comment Share on other sites More sharing options...
Rollie715 Posted April 27, 2006 Author Share Posted April 27, 2006 If your coolant temp sensor is working fine and actuallly functioning..you will notice idle up at cold start..after engine is warm..it will drop to normal idle..if it is hoovering above normal idle..that will be the problem.....i run a few ea82t,s and the oxygen sensor does not make the cel come on..if you disconnect it.... and will not let black smoke belch out the rear when disconnected..diesel will do this though..lol:lol: so i would look elsewhere for the problem.....cheers Hmmm. Coolant temp sensor could be it. I do notice a high idle problem, somtimes as high as 3000 rpm. Adjusting the throttle stop down to the limit where the butterfly is all the way closed still results in a 2000+ rpm idle when hot. Is this the same sensor used to run the dash temp gauge, because the gauge seems to go up and down normally with temperature? Where is the above mentioned temp sensor located? Thanks for the continued input. When we get this one solved the rest of the engine should run just about perfect considering all the new parts and adjustments I've been doing. Rollie Quote Link to comment Share on other sites More sharing options...
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