Honda Car Forum

Last summer, my '94 GS-R started having a problem with a very light
knock under load at low rpm. The problem has slowly gotten worse in
that the knock is noticeably heavier now. Not really a problem - yet
- but it has gone from curiosity to annoyance.
The car has 145K of hard use. Generally maintained well but may be
coming due for some routine items and about 30K since its last valve
adjustment. I use Mobil 1 but I only change it twice a year. Engine
all original and stock except for a header to replace the noisy
A-pipe. Other than the knock, the engine runs great like always.

Any ideas?

Gordon McGrew <gmcgrew@mindspring.com> wrote in
news:8bk112h3ff7mu0su30t96klm6dqphsea0j@4ax.com:

>
>
> Last summer, my '94 GS-R started having a problem with a very light
> knock under load at low rpm. The problem has slowly gotten worse in
> that the knock is noticeably heavier now. Not really a problem - yet
> - but it has gone from curiosity to annoyance.
> The car has 145K of hard use. Generally maintained well but may be
> coming due for some routine items and about 30K since its last valve
> adjustment. I use Mobil 1 but I only change it twice a year. Engine
> all original and stock except for a header to replace the noisy
> A-pipe. Other than the knock, the engine runs great like always.
>
> Any ideas?
>



Try Premium gas.

Check ignition base timing.

Motorvac service to remove deposits from combustion chamber.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

On 10 Mar 2006 01:51:12 GMT, "TeGGeR®" <tegger@tegger.c0m> wrote:

>Gordon McGrew <gmcgrew@mindspring.com> wrote in
>news:8bk112h3ff7mu0su30t96klm6dqphsea0j@4ax.com :
>
>>
>>
>> Last summer, my '94 GS-R started having a problem with a very light
>> knock under load at low rpm. The problem has slowly gotten worse in
>> that the knock is noticeably heavier now. Not really a problem - yet
>> - but it has gone from curiosity to annoyance.
>> The car has 145K of hard use. Generally maintained well but may be
>> coming due for some routine items and about 30K since its last valve
>> adjustment. I use Mobil 1 but I only change it twice a year. Engine
>> all original and stock except for a header to replace the noisy
>> A-pipe. Other than the knock, the engine runs great like always.
>>
>> Any ideas?
>>
>
>
>
>Try Premium gas.

I should have mentioned that I only use premium per Honda reco.

>
>Check ignition base timing.

Good idea.

>Motorvac service to remove deposits from combustion chamber.

Is there any way to determine if this is needed?

Thanks for the suggestions.

In article <pcn4125kbv5g504spkkttts4diu650bbge@4ax.com>, Gordon McGrew
<gmcgrew@mindspring.com> wrote:

> On 10 Mar 2006 01:51:12 GMT, "TeGGeR®" <tegger@tegger.c0m> wrote:
>
> >Gordon McGrew <gmcgrew@mindspring.com> wrote in
> >news:8bk112h3ff7mu0su30t96klm6dqphsea0j@4ax.com :
> >
> >>
> >>
> >> Last summer, my '94 GS-R started having a problem with a very light
> >> knock under load at low rpm. The problem has slowly gotten worse in
> >> that the knock is noticeably heavier now. Not really a problem - yet
> >> - but it has gone from curiosity to annoyance.
> >> The car has 145K of hard use. Generally maintained well but may be
> >> coming due for some routine items and about 30K since its last valve
> >> adjustment. I use Mobil 1 but I only change it twice a year. Engine
> >> all original and stock except for a header to replace the noisy
> >> A-pipe. Other than the knock, the engine runs great like always.
> >>
> >> Any ideas?
> >>
> >
> >
> >
> >Try Premium gas.
>
> I should have mentioned that I only use premium per Honda reco.
>
> >
> >Check ignition base timing.
>
> Good idea.
>
> >Motorvac service to remove deposits from combustion chamber.
>
> Is there any way to determine if this is needed?
>
> Thanks for the suggestions.

The first thing that you should do is to adjust the timing--If you have
never done this before--have a mechanic do it for you.

If that does not solve the problem, you should have a complete tune-up.
Mechanics use a Diagnostic Computerized Engine Tester when performing a
tune-up. That means the mechanic can easily find and repair any problems
that are the cause of the "knock". When I had a "knock" problem--I solved
it by adjusting the timing but there are other causes. Also, attempt to find
out whether or not your car has a "knock sensor". If it does have a knock
sensor--it might need to be replaced.

--
NEWSGROUP SUBSCRIBERS MOTTO
We respect those subscribers that ask for advice or provide advice.
We do NOT respect the subscribers that enjoy criticizing people.

Your GS-R has anti-knock sensors. This means it retards the timings when the
car pings. Usually, the computer should throw a engine code when they
malfunction, as it's doing in your case. Maybe something else is wrong with
your engine? Too much carbon in the intake? worn plugs? cables? distributor
cap?


"Jason" <jason@nospam.com> wrote in message
news:jason-1103061224120001@66-52-22-70.lsan.pw-dia.impulse.net...
> In article <pcn4125kbv5g504spkkttts4diu650bbge@4ax.com>, Gordon McGrew
> <gmcgrew@mindspring.com> wrote:
>
>> On 10 Mar 2006 01:51:12 GMT, "TeGGeR®" <tegger@tegger.c0m> wrote:
>>
>> >Gordon McGrew <gmcgrew@mindspring.com> wrote in
>> >news:8bk112h3ff7mu0su30t96klm6dqphsea0j@4ax.com :
>> >
>> >>
>> >>
>> >> Last summer, my '94 GS-R started having a problem with a very light
>> >> knock under load at low rpm. The problem has slowly gotten worse in
>> >> that the knock is noticeably heavier now. Not really a problem - yet
>> >> - but it has gone from curiosity to annoyance.
>> >> The car has 145K of hard use. Generally maintained well but may be
>> >> coming due for some routine items and about 30K since its last valve
>> >> adjustment. I use Mobil 1 but I only change it twice a year. Engine
>> >> all original and stock except for a header to replace the noisy
>> >> A-pipe. Other than the knock, the engine runs great like always.
>> >>
>> >> Any ideas?
>> >>
>> >
>> >
>> >
>> >Try Premium gas.
>>
>> I should have mentioned that I only use premium per Honda reco.
>>
>> >
>> >Check ignition base timing.
>>
>> Good idea.
>>
>> >Motorvac service to remove deposits from combustion chamber.
>>
>> Is there any way to determine if this is needed?
>>
>> Thanks for the suggestions.
>
> The first thing that you should do is to adjust the timing--If you have
> never done this before--have a mechanic do it for you.
>
> If that does not solve the problem, you should have a complete tune-up.
> Mechanics use a Diagnostic Computerized Engine Tester when performing a
> tune-up. That means the mechanic can easily find and repair any problems
> that are the cause of the "knock". When I had a "knock" problem--I solved
> it by adjusting the timing but there are other causes. Also, attempt to
> find
> out whether or not your car has a "knock sensor". If it does have a knock
> sensor--it might need to be replaced.
>
> --
> NEWSGROUP SUBSCRIBERS MOTTO
> We respect those subscribers that ask for advice or provide advice.
> We do NOT respect the subscribers that enjoy criticizing people.
>
>
>

Nightd00d wrote:
> Your GS-R has anti-knock sensors. This means it retards the timings when the
> car pings. Usually, the computer should throw a engine code when they
> malfunction, as it's doing in your case. Maybe something else is wrong with
> your engine? Too much carbon in the intake? worn plugs? cables? distributor
> cap?
>
>
> "Jason" <jason@nospam.com> wrote in message
> news:jason-1103061224120001@66-52-22-70.lsan.pw-dia.impulse.net...
>
>>In article <pcn4125kbv5g504spkkttts4diu650bbge@4ax.com>, Gordon McGrew
>><gmcgrew@mindspring.com> wrote:
>>
>>
>>>On 10 Mar 2006 01:51:12 GMT, "TeGGeR®" <tegger@tegger.c0m> wrote:
>>>
>>>
>>>>Gordon McGrew <gmcgrew@mindspring.com> wrote in
>>>>news:8bk112h3ff7mu0su30t96klm6dqphsea0j@4ax.co m:
>>>>
>>>>
>>>>>
>>>>>Last summer, my '94 GS-R started having a problem with a very light
>>>>>knock under load at low rpm. The problem has slowly gotten worse in
>>>>>that the knock is noticeably heavier now. Not really a problem - yet
>>>>>- but it has gone from curiosity to annoyance.
>>>>>The car has 145K of hard use. Generally maintained well but may be
>>>>>coming due for some routine items and about 30K since its last valve
>>>>>adjustment. I use Mobil 1 but I only change it twice a year. Engine
>>>>>all original and stock except for a header to replace the noisy
>>>>>A-pipe. Other than the knock, the engine runs great like always.
>>>>>
>>>>>Any ideas?
>>>>>
>>>>
>>>>
>>>>
>>>>Try Premium gas.
>>>
>>>I should have mentioned that I only use premium per Honda reco.
>>>
>>>
>>>>Check ignition base timing.
>>>
>>>Good idea.
>>>
>>>
>>>>Motorvac service to remove deposits from combustion chamber.
>>>
>>>Is there any way to determine if this is needed?
>>>
>>>Thanks for the suggestions.
>>
>>The first thing that you should do is to adjust the timing--If you have
>>never done this before--have a mechanic do it for you.
>>
>>If that does not solve the problem, you should have a complete tune-up.
>>Mechanics use a Diagnostic Computerized Engine Tester when performing a
>>tune-up. That means the mechanic can easily find and repair any problems
>>that are the cause of the "knock". When I had a "knock" problem--I solved
>>it by adjusting the timing but there are other causes. Also, attempt to
>>find
>>out whether or not your car has a "knock sensor". If it does have a knock
>>sensor--it might need to be replaced.
>>
>>--
>>NEWSGROUP SUBSCRIBERS MOTTO
>>We respect those subscribers that ask for advice or provide advice.
>>We do NOT respect the subscribers that enjoy criticizing people.
>>
>>
>>
>
>
>
I already told him to look for a vacuum leak (Manifold?) - Had one
exactly like this myself and had to work it out.... no codes, lights,
help from a NG, etc, just crackly acceleration and crappy idle...
Dealer couldn't even correct it, although they said, they knew what it
was and charged me a lot to "adjust the problem".