lack of power when cold under load.

glenn evans · Postby **glenn evans** » Sat Mar 20, 2010 10:12 am

hi, we have a 98 1.8 rs done 150000kms- starts fine when cold , but on attempting to back up our drive way, which is on a slope she does not want to go, unless you use lots of revs and drag the clutch, does not stall but idle is uneven around 6-700rpm when cold. i have changed the plugs and the plug leads to no avail, the plugs are dry black at the base.On further investigation i have discovered that the breather tube that runs from the back of the inlet manifold to the exhaust is missing on the parts list this is the egr pipe which is located under the egr valve could this be the problem? the car runs ok the rest of the time.

sliq · Postby **sliq** » Sat Mar 20, 2010 10:48 am

where are u located?

glenn evans · Postby **glenn evans** » Sat Mar 20, 2010 10:53 am

auckland nz

Alex · Postby **Alex** » Sat Mar 20, 2010 10:51 pm

base idle speed?

Steampunk · Postby **Steampunk** » Sun Mar 21, 2010 12:45 am

Alex wrote:base idle speed?

it idles at 600-700RPM? If so, then of course it will idle uneven as idle speed should be approx 900-1,000RPM

Check your timing.

Description of plugs seems like they are ok.

Is the car revving but not moving accordingly? If so, then maybe its a slipping clutch? But at 150,000km it should still be ok unless it's hard a harsh life.

Alex · Postby **Alex** » Sun Mar 21, 2010 11:12 am

http://www.miata.net/garage/ignition.html#idle
Give that a try for fixing the idle

not sure about the lack of power though

93_Clubman · Postby **93_Clubman** » Sun Mar 21, 2010 1:11 pm

glenn evans wrote:On further investigation i have discovered that the breather tube that runs from the back of the inlet manifold to the exhaust is missing on the parts list this is the egr pipe which is located under the egr valve could this be the problem?

Apparently it's possible, but not legal, to remove EGR, if it's done properly. Does yours appear to have been disabled or removed properly, or is it just a missing pipe?
http://www.miataturbo.net/forum/t15625/
Google "miata egr removal" or "miata egr delete" for more info.

glenn evans · Postby **glenn evans** » Sun Mar 21, 2010 2:46 pm

thanks, no problem with idle once warm sits on 900 nicely (even more so since i replaced the ignition leads $70 off local dealer genuine mazda , looks like the egr tube has just been removed,i should plug it ?am running ngk bkr5E 11 & she runs on bp98oct or if unavailable mobil 97.8 so there it is oh 150000 kms ex land of rising sun

93_Clubman · Postby **93_Clubman** » Mon Mar 22, 2010 12:07 pm

glenn evans wrote:looks like the egr tube has just been removed, i should plug it?

If there's a possibility it could vent to the engine bay you should either replace it or plug it. If the problem persists, worth keeping in mind that NB8A coilpacks often require replacement.