DSSKing

My 88 L98 with 129,000km is running rich..... computer on the dash claims 15 litres/100K. You can smell it's rich....... question is what are the common parts to check/replace? Plugs, wires are in, cap and rotor tonight. I can't see the cap/rotor causing that.

Any suggestions? O2 sensor has been replaced too.

Much Appreciated.

65Z01

If it has OBD1, use the method on my site to see if the ECM is going & staying closed loop.

If not, check the O2 sensor and the coolant temp sensor in the front of the intake base. Both of these must be functioning properly for the ECM to be in closed loop mode.

If these are ok, check for vacuum leaks or air leaks in the exhaust manifold before the O2 sensor.

DSSKing

65Z01, please direct me to your site?
Thanks

65Z01

Just click on "1988 Z01 #65 Site" above.

LaVidaLoca

Two things to check:

Is fuel pressure holding at the fuel rail or is it rapidly dropping when you shut down? If it drops you might have leaking injectors.

Check the Block Learn with a scanner. Normal range is 115-140. If you are near the low end (115) the ECM is trying to lean out to correct a rich condition and could also be related to injectors leaking.

Those two things should help pinpoint the problem. You can also pull the plugs and see if one or more are running richer than the others and if they have a strong gas odor or if they are wet with fuel.

My bet would be injectors.

:cheers:

larrybsp

Check to see if you haven't blown a fuel pressure regulator diaphragm. Pull one of the vacuum lines. If you smell gas its the diaphragm.

Rick86

Everything I read says normal BLM is 128 +/- 6, my BLM stays around 119. Integrater stays within 128 +/- 6

Hope your right I've trying to figure why my car runs rich.

would a cam change cause it to run rich?