Hesitation at 100km/h, NA6

mr_rotary · Postby **mr_rotary** » Sun May 18, 2008 8:31 pm

I seem to have this hesitation at around 90-100km/h and also at higher RPM in lower gears, such as 3rd gear 60km/h. What it's basically doing is when cruising at 100km/h I try to accelerate and then all of a sudden the car will surge off. It's sometimes hard to keep a consistant speed.

I have cleaned at least 4 times the air/idle screw on the throttle body and once sprayed carby cleaner in the front of the throttle body. Today I have changed the fuel filter. Although it is smoother once the fuel filter was changed, it still has that hesitation.

Any ideas on what will fix this?

Fatty · Postby **Fatty** » Sun May 18, 2008 9:09 pm

time for some new plug leads?

mr_rotary · Postby **mr_rotary** » Sun May 18, 2008 10:50 pm

Fatty wrote:time for some new plug leads?

Replaced with Genuine Mazda leads back in September 05'. I'll get my hands on a Ohnmmeter to test them out.

MxJadeMonkey · Postby **MxJadeMonkey** » Mon May 19, 2008 12:54 am

I will go for the new plugs option mate, try a standard NGK or Bosch plug.

Rotary · Postby **Rotary** » Mon May 19, 2008 8:47 am

is the hessitation more of a stumble(flat spotting) or just a delayed response?

If flat spoting, then definately a fueling or ignition Prob.

If its a delay only, then may not be either.
but how much of a delay?

im not up to speed with your setup, B6 or BP, Mods etc.

if B6 then check the operation of the Vane Airflow meter,(or any other posible airflow restrictions) . It wouldn't be throtle body as it cable operated and you would feel any improper operation.

Cant hurt to change plugs if there nearly due, but your problem may be elsewhere if just a delay.

Also has the car lost any power?, is the fuel consump. higher than normal?

mr_rotary · Postby **mr_rotary** » Mon May 19, 2008 10:21 am

Rotary wrote:is the hessitation more of a stumble(flat spotting) or just a delayed response?

Delayed response. I have no problems at all going to redline in each gear though.

Rotary wrote:If its a delay only, then may not be either.
but how much of a delay?

Hard to explain. I need to keep pressing down on the accelerator and then it will suddenly accelerate.

Rotary wrote:im not up to speed with your setup, B6 or BP, Mods etc.

B6 (1.6L) with racing beat air filter, extractors and reguarly serviced, that's it.

Rotary wrote:Cant hurt to change plugs if there nearly due, but your problem may be elsewhere if just a delay.

Changed with NGK plugs not so long ago.

Rotary wrote:Also has the car lost any power?, is the fuel consump. higher than normal?

All seems normal....power may seem a little flatter

ampz · Postby **ampz** » Mon May 19, 2008 10:48 am

How is your fuel comnsumption?
If it is a little high, then I would be suspecting your o2 sensor is stuffed and Flooding when going into open loop mode (around 3500-4000 rpm or about 100K in 5th)

New sensor (single wire) is around $40 from Repco.

Do a search on here there should be part numbers somewhwere.

Cheers
NJ

mr_rotary · Postby **mr_rotary** » Mon May 19, 2008 11:00 am

ampz wrote:How is your fuel comnsumption?
If it is a little high, then I would be suspecting your o2 sensor is stuffed and Flooding when going into open loop mode (around 3500-4000 rpm or about 100K in 5th)

New sensor (single wire) is around $40 from Repco.

Do a search on here there should be part numbers somewhwere.

Cheers
NJ

I think you may be on the money here as that's exactly around the RPM it has been doing this. I had plan to replace this sensor once day as I heard it does make a difference when they are replaced.

I'll give this a go and get back on whether it worked or not

Boags · Postby **Boags** » Mon May 19, 2008 12:24 pm

Check my write-up in the Tech Archive on installing a 4 Wire O2 sensor...

mr_rotary · Postby **mr_rotary** » Mon May 19, 2008 12:37 pm

Boags'MX5 wrote:Check my write-up in the Tech Archive on installing a 4 Wire O2 sensor...

I can't seem to find it there and the 'search' is broken when used with your username! Do you have a link?

Boags · Postby **Boags** » Mon May 19, 2008 2:51 pm

mr_rotary wrote:
Boags'MX5 wrote:Check my write-up in the Tech Archive on installing a 4 Wire O2 sensor...

I can't seem to find it there and the 'search' is broken when used with your username! Do you have a link?

The link in that thread got swallowed up by the interwebs... So the thread is useless. Just do a search on google for 4 wire 02 sensors on google and look for someone else's write-up. :frown:

Sorry to give false hope.

Rotary · Postby **Rotary** » Mon May 19, 2008 5:14 pm

Agree with the above(O2), as its sounds like a very short delay,

mr_rotary · Postby **mr_rotary** » Mon May 19, 2008 8:39 pm

Boags'MX5 wrote:The link in that thread got swallowed up by the interwebs... So the thread is useless. Just do a search on google for 4 wire 02 sensors on google and look for someone else's write-up.
Sorry to give false hope.

http://www.miata.net/hakuna/0004/h0001.htm

Does anyone have the Bosch model number, I can only find the NA6 in the Bosch online PDF manual?

If not, this may do the trick?
http://cgi.ebay.com/ebaymotors/O2-OXYGEN-SENSOR-BOSCH-Mazda-Miata-03-99-97-94_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247QQcategoryZ33557QQihZ022QQitemZ350035547624QQrdZ1QQsspagenameZWD1V