Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Geo Metro Engine Questions



  • zendenzenden Posts: 62
    First did you test for codes by inserting a fuse? This will tell us pertinent info to proceed. So in order to proceed you will need to test for codes you wont hurt anything on the system. Then report the code to me.
    Because there are other components on the throttle body with similar colored wires, I need to know where this component with the clip is located. On the throttle body with the air breather cover removed and standing in front of the car; looking at it from above, the Temp. Sensor would be in the rear of the throttle body with the wires plugging into it from the driver side. Are we talking about the same component? If not please state the exact location.
  • bobkat2bobkat2 Posts: 6
    Thanks again for the help. I will get the codes tomorrow. I didn't think they would be of much help because I have plugged and unplugged so many devices. I will reset the check engine light codes and run it to see if any new codes appear. I read that you can reset the light by removing the tail lamp fuse but I don't know which fuse that is.
    It sounds like you are talking about the same sensor. It is toward the back of the t/b but screws in horizontally from right to left as you face the engine from the front of the car. Is it possible to post an image on this board?
  • bobkat2bobkat2 Posts: 6
    I went out today at about 2:30 pm and the car started pretty good. It chugged a little bit before it ran good. I took the negative battery cable off for about a minute and then checked the engine codes and it read 12. I started it again and shut it off and checked the code again and it still just read 12.
  • bobkat2bobkat2 Posts: 6
    Zenden, thanks for the reply. I got your email but didn't realize that you had left that little message about how it was too much info to post here. I thought that maybe you were still gone or something. It's late Friday night now so if you let me know a good time to call I will try to call then if you still want me to. Thanks again, Bob.
  • zendenzenden Posts: 62
    I have to work tomorrow and it is to late now so call me tomorrow any time, then we will set up a time to go over it in depth, after work. It is very difficult if not imposable to diagnose cars in a forum.
  • I recently purchased a 1989 metro, it runs fine...sputters a little at takeoff sometimes but idles high, i've read posts about the TPS throttle position sensor and wonder if that is the usual suspect, i have only been getting about 34mpg this low? the territory i drive is fairly undulating and requires some downshifting at freeway speeds....any help would be appreciated...
  • zendenzenden Posts: 62
    To know what your gas mileage should be and to help diagnose it is need to know, how many cylinders, and dose it have stick shift, with or without AC.
    The spit and sputter can be caused by a TBS, but not the high idle. A high idle is usually caused by a vacuum leek; this is what I would be looking for first; most likely there is too much air coming in from somewhere! It could also cause that spit and sputter, it would also cause a lot of extra gas consumption.
    Many things can be a cause of to much air; sticking Throttle bodies, a bad PCV valve, a blown head gasket, (Yes! with out having any other symptoms of a blown head gasket) As in! Oil in the water; water in the oil; water coming out the exhaust pipe, or flames shooting out of the head gasket, and or over heat problems. It could have a bad intake gasket, bad idle control valve, a bad A/C idle control motor that’s sticking, some one could have adjusted the factory set idle to compensate for a primary problem in the past, there could be carbon built up around the throttle body, the Idle control valve could be sticking from carbon build, or it could be bad, this would be a good possibility. All of these things are possible and must be part of the process of elimination when diagnosing.
    First closely listen with your ear for an air leek while the engine is idling; If you don’t here one, then replace the PCV valve, if the trouble is still there do a vacuum test with the idle as low as specified, if the vacuum is still low find the leak it will becoming from somewhere. The 1989 GEO metro 3 Cyl. 5spd with a full tank of gas with no passengers on a flat road at 55 MPH will produce over 60 MPG. City driving could give you up to 47 MPG. If you are equipped with an automatic Trans you will never produce that much efficiency. I hope that I have helped you in some way, it is very difficult to diagnose on line, if not impossible at times
  • Hello and thank you for some tips...the car is a 3 cylinder with 5 speed and no a/c, i will check these and report my findings....thank you
  • car will start just fine and run until the engine gets warm then car will die and not start until engine is COLD. Any ideas why?
  • zendenzenden Posts: 62
    need more info, sounds like EGR related, Run OBD test!
  • I just got a 2000 Chev. Metro, 3 cyl. I limped home with it from the auction. The air filter bracket was reversed. Compression is 120 lb. It has a surging idle from 2 to 3000. Mechanic said to try replacing the idle motor, but it's still the same after I put in one from the junk yard. I sprayed carb cleaner to check for leaks. EGR valve is free and holding a vacuum. Car has 153,000, seems ok otherwise. It shows no engine codes.
  • zendenzenden Posts: 62
    a vacuem test would tell if you had multable burnt valves; it could be!! one because it has low compression; Metro 3 cyl engines are knowen for this! Are they all within 15% of each outher, over the total avrager?
  • Compression test was close to 120 on all three. I guess I'm still thinking of old VW's where that would be good compression.
  • zendenzenden Posts: 62
    I checked the specs. on your 2000 Metro 3 cyl Normal Compression : 199 PSI, minimum 156 PSI
  • pcthurmanpcthurman Posts: 1
    I am buying a 93 the engine is bad so I purchased a 90 model engine I see some different sensors on both can I drop it in or do I need to swap everything?????
  • mageomageo Posts: 3
    I recently purchased an 89 metro and it pretty much runs fine except when I try to travel in 5th gear. As soon as I reach the appropriate speed for 5th gear and try to put it in it seems to bog and starts to decelerate as if it's almost to high a gear, but I can't maintain speed or accelerate. I can leave it in 4th and climb up to 65 no problem. Could this be because of an EGR or PCV clog that effects the amount of load the car can push at 55pmh in that gear, or fuel filter?
  • mageomageo Posts: 3
    Hello, I saw your response and you seemed like you knew a thing or two about those metro's. I have an 89 and all seems to run fine except when traveling in 5th gear. I can run the car up to 65-70 in 4th no problem but when I try to shift to 5th it almost acts like it bogs and starts to decelerate, not maintaining speed or accelerating at all. What do you think the problem could be?

  • zendenzenden Posts: 62
    It could be low vacume due to a clogged catalytic converter but then it would have a loss of power through the whole power range. How long has it been doing this? How long have you had it do you know the car; or GEO's and how they feel?; and is this problem getting worse? Is it possible that the tires are to tall for that car are they 12 inch tires on the car? Is it possible that it has the FXI trans in it, that would throw the speedo off and be making you go faster then what it shows; in turn putting an extra strain on the eng,
    It could be the fuel filter or pump; or the pump pressure regulator, it is under the air breather on top of the throttle body toward the front passengers side. it is round with about 3 screws. If the fuel pressure is low when under a load due to the regulater, you could replace for about $40. parts, or clean it out with spray cleaner; watch out most likely its spring loaded and a small ball check valve seated. Make sure that you seal it properly. If it where a fuel supply problem witch it sounds like it could be, then most likely when you are on the highway pulling a hill as it has that loss of power slows down if you where to put it to the floor and hold it then immediately down shift and hold it to the floor again , this would be the extreme test for the fuel supply system. The car will then fall flat on its face, chug and maybe even come to a stop due to lack of fuel pressure, or low fuel flow when needed; unless you where to let off of the gas to let the pressure build back up.
    If it where a cat clog, then it could be tested with a vacuum gage at idle; and if it where a cat clog then there would be a primary reason for the clog, like low eng temp as in bad thermostat( running to cold, low ignition timing; is many times the reason for the cat clog! all of this would be a symptom of bad MPG for a long time to clog it. Its hard to fix a car online so sorry for thinking out loud! but hopefully it is what you needed to give you some ideas that will help. Most people on here will try to fix there own or get pointed in the general direction, then speak to other mechanics about it. Ask away I will do my best when I can to help.
  • zaken1zaken1 Posts: 556
    I've never heard of the fuel pressure regulator on a Metro giving trouble. And the PCV valve and EGR valve would have a much greater effect on running at low speeds and in the lower gears than they would in 5th at high speed.

    I believe it is one of 5 possibilities: poor compression, excessive resistance in the plug wires, defective distributor cap or rotor, clogged fuel filter, or worn or unsuitable spark plugs.

    The compression pressure in the 3 cylinder Metro should be 195psi. If it is lower than 180psi in any cylinder; the engine cannot be made to perform properly.

    The spark plug wires should have no more than 1,000 ohms resistance for each inch of wire length. (They measure 500 ohms per inch of length when new.)

    The distributor cap can create problems if the carbon button in the center of the inside edge is missing or damaged. There also can be problems if the inside surface of the cap has any carbon tracks or lines on it; or if it is coated with dirt on either the inside or outside. It must be kept surgically clean. The same goes for the rotor.

    The fuel filter should be replaced, as it is the least commonly maintained item on that car; and is thus the most likely to need replacement. And it will have the greatest effect on running in 5th gear.

    Metro engines are astonishingly sensitive to spark plug brand and condition. Most people install NGK plugs in that engine; just because they are such a popular brand. But in the 17 years I have owned my 1990 Metro, and in the 30 plus years that I have been a diagnostic, fuel and electrical systems specialist; I have never seen a worse spark plug choice for the Metro than NGK plugs!!! In this car, I would recommend either Bosch # 7900 Super Plus (which is a fairly new part number, and may be difficult to locate), or Champion # 332 (RN7YC). The gap in these plugs should be set to .043". These plugs are slightly colder than the recommended ones; and my experience is that they work better, for that reason.
  • zendenzenden Posts: 62
    What you said sounds like good advice! As for the PCV and EGR comment that I made, that was in refrance to anouther post; Not this (5th grear struggle post). He could also check the resistance on the ignition coil.
Sign In or Register to comment.