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Loss Of Power.. anyone help?

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    Loss Of Power.. anyone help?

    Alright guys, so since I got my CB7 its been a really smooth time to time on replacing parts as the previous owner did not do any maintenance on the car.. So my problem is that the car Loses power on acceleration. The following parts had been replaced .. Ignition, cap, wires, and all of the injectors (4) , and still I'm losing power.. like what the heck? The timing belt got done about 2 months ago, but the person who did the job, dint do it right so my car now sounds like the pistons are hitting the head or something like that. I had not got that checked because a close friend of mine told me that is not very important. But the more I accelerate the car, the more the pistons sound and the more power the car loses.. so I'm asking myself, can it be the Timing belt being replaced wrong or the fuel pump? I still had not got the fuel pump checked but I want to get an idea first. any help would be really appreciated it because its driving me nuts
    Last edited by Boriiboss; 01-22-2014, 05:52 PM.

    #2
    A big picture of your car is not necessary for us to help you with your problem.

    Has this problem been happening since the timing belt was done? If the belt is off by a tooth, you will notice a loss in power... and potentially internal engine damage.
    Was your ignition timing set properly after the timing belt job, and after the ignition components were changed? (I don't know what "ignition" means... did you replace your distributor?)
    Is your check engine light on? Does it ever come on? Although the timing belt seems to be the problem, another common power loss culprit is the o2 sensor. If you replace that, do so only with a Denso or NTK part. No Bosch.






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      #3
      Well thanks, I thought putting a pic of my car would make my post look better, sorry I apologize.. That problem appeared after 1 month of replacing the timing belt, Yeah that's what I meant instead of ignition, no the check engine light never comes on. and yes, the distributor got replaced along with the wires.. also, the failure starts once the engine is fully warm... I have to step on the gas so it will respond instead of shutting down.. i cannot get into the high way unless I travel at 40+.. I cannot step on the gas because then it will start that power loss..

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        #4
        Does your check engine light work? Can you get the car up to about 55mph?

        Since it only occurs when the engine is warm, that makes it sound more like the o2 sensor. When the engine is cold, the ECU is running in "open loop mode". Essentially, it's fueling based on preset fuel maps. When the engine reaches operating temperature, it switches to "closed loop mode", which calculates fueling based on oxygen sensor input. When the sensor is beginning to fail, these readings are incorrect... and fueling gets screwed up.

        I suggest replacing that o2 sensor with one of the brands I mentioned above.
        If you want another way to check, try unplugging the sensor. Tie the wire back (so it doesn't rest on the hot exhaust pipe), and drive around. The check engine light should come on, and the car should drive normally.


        As for the picture... save it for the image gallery. Don't post pictures in the technical section unless they pertain to your question. A full picture of your car is just inviting off-topic commentary in this thread, which is of no help to you, and certainly won't help anyone who has your same problem in the future. Nobody wants to weed through that nonsense.






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          #5
          Yeah I can get to 55 if I go easy on the gas.. But if I step on it, it will start... Today I accelerated when someone was turning and it just chokes, I will try to make it to my local auto parts, ask if they have any of those brands and see the results.. Thanks !!

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            #6
            It really sounds like your camshaft timing is off via the timing belt. Years ago my belt jumped 2 teeth, light throttle accel was fine but WOT accel was a bunch of noise and went nowhere. I'm honestly not sure what the limit is for skipped teeth w/o internal damage but I do know 2 teeth is okay.

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              #7
              That's strange. I'd assume having the timing off by a tooth or two would produce problems at all times; idle, light throttle, or full throttle.

              If it can indeed be a full throttle issue only, then definitely check that.






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                #8
                Also, i forgot to mention in the first post that my idle gauge gets really crazy whenever i step on the gas, the more it reaches 3 to 5, the more the engine loses power.. my brother and I had done a couple of hypothesis and we discovered that its something electrical.. and of course what you guys mentioned, the O2 Sensor.. I will be going to the Parts Center Cuz it annoys me

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                  #9
                  I notice you mentioned that you replaced most of your consumable ignition components, but I saw that you didn't mention your plugs. Even if you have replaced them, try to get a "read" off of them (discoloration, deposits, etc). They can tell you a lot about what your engine is doing.

                  And of course, if you haven't replaced them...DO IT!

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                    #10
                    Idle gauge? If you're stepping on the gas, you're not at idle.
                    An erratic tachometer could be an indication of a failing ignitor... which could also be a potential cause for your problems.






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                      #11
                      i meant the first gauge "1 2 3 4 5" whenever I hit the gas a little bit, it goes up and keeps on bouncing.. ?

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                        #12
                        Guys anyone help? I got a distributor but it was from ebay which costed $70.. could it be fuel pump or distributor? injectors got replaced not too long ago.

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                          #13
                          I think your timing is retarded via the timing belt... Time to get the covers off and take a gander. Get a timing light...

                          Also I don't think anyone has said MAP or TPS yet, but they can both cause similar problems.
                          Last edited by wildBill83; 09-18-2014, 07:45 PM.

                          Comment


                            #14
                            Originally posted by Boriiboss View Post
                            so my car now sounds like the pistons are hitting the head or something like that. I had not got that checked because a close friend of mine told me that is not very important.
                            Then never listen to that person again. It's not unlikely that the noise is the pistons 'kissing' the valves (hopefully nothing heavier, which could mean bent valves). Suggestions relating to the timing belt being 'off' by a tooth or two may well be correct. If so then this will affect performance directly, and also indirectly since the cam timing will substantially affect the ignition timing.
                            Regards from Oz,
                            John.

                            Comment


                              #15
                              Originally posted by deevergote View Post
                              That's strange. I'd assume having the timing off by a tooth or two would produce problems at all times; idle, light throttle, or full throttle.
                              My (limited) understanding is that having the cam timing off by (say) a tooth can increase torque at one end of the rev range but lose it at the other end. So, if the cam timing were off you might pick up more torque at low rpm but the engine falls on it's face at higher rpm, or vice versa, depending. This is likely very over-simplified and also affected by the specifics of the cam grind and the fluid dynamics of the exhaust and inlet tracts (etc...).

                              This is perhaps simpler with a single cam motor where the timing is either correct or advanced or retarded on all cam lobes (three possibilities). For twin cam engines it could be either or both the inlet or exhaust cams right or wrong, so the scope for different affects increases hugely.

                              Both camshafts could be correct, both could be wrong (advanced or retarded), one could be correct but one retarded, one could be correct but one advanced, the other could be correct but the other retarded or advanced. So for twin cam engines (and assuming a camshaft to be off by one tooth only), the possible range of incorrect timings amount to nine differing combinations of correct, advanced, retarded. With nine possible different affects on the power band, ignoring ignition timing...
                              Regards from Oz,
                              John.

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