My Pintos HC levels are to high to pass the MOT they tried it twice but it the second time the readings where even higher.
1389 ppm first test
1620 ppm second test 40 minutes later.
The plugs and leads seem fine although will change them before next re-test but is there any known problems with injection Pintos that would cause high HC on emissions?
If the fuel rail / injector seals are like the early zetecs I would start with possible air leaks there.
HC is unburnt fuel or oil, what is you C O reading ? It may be as simple as adjusting the mixture but I would start by checking and adjusting the
valve clearances when the engine is cold . Iíve had problems in the past with Pinto valve stem oil seals causing high HC . No need to remove the head
, they can easily be changed . Restricted crankcase breathers , incorrect timing , valve or ignition , incorrect plug gaps, misfire , air leaks ,
dirty air filter , engine not up to normal operating temperature will all cause high HC . Check the basics first but the fact the second reading was
higher I would look at changing the valve stem seals first. Had the engine cooled down for the second test?
[Edited on 8/5/19 by rusty nuts]
Unburned hydrocarbon emissions are commonly caused by :
1) An excessively rich mixture. If that were the case you would also have failed on CO emissions and the exhaust would be stinking.
2) One or more cylinders not firing, or at least not firing every cycle. Check ignition (plugs, leads, distributor cap, rotor arm and coil) and compression.
I forgot to mention I was planning on doing the valve stem seals as well as the plugs and leads. In fact the new CVH stem seals arrived earlier today.
I'm hoping over the weekend I'll have the plugs, leads, stem seals and valve gaps sorted and that will cover the common stuff. I was just checking if there was any falls more specific to the injection pintos.
I'll have a look at the CO reading and post them up later but it did pass on these.
CO readings were
Is it on a normal reg or a q plate? If itís a q then it should be just a visual smoke check
Unless things have changed in the last 3 years since I last tested you are allowed to test at up to 2,000 RPM if the HC fails at idle which is likely to drop the reading