Bill Ball

The search begins. It's in my garage after a 40 mile jaunt. Ran very well on the way home. Mild steering wheel shimmy at 75-80 that went away at higher speeds. Will look at the rack and tie rods and probably have the wheels rebalanced. As long as you keep it over 85, it's smooth. Vroom!

SeanR

Kinda what we already do, but we get to smother that smell with brake clean and oil.

Bill, good luck, I'm sure you will be able to find the cause. Keep us updated. FWIW, my '88 is due for it's last inspection this month and I have a keen feeling that she won't pass (last year NOX passed by 3 points. I pray that it will this year. So if you find a quick fix, a lot of us will be grateful.

blown 87

Wont next year be your last year for testing on a 88?

SeanR

Yes, thank God.

jeff spahn

Move to a state with more cows than people. Problem solved. We don't have emission testing here. Only 2 Million people in whole state. $50 to register my car every year too is a bonus.

Bill Ball

CA is a rough place smog-wise for cars. NOX is often the problem child and many states do not test for it. CA has for decades.

Anyway, quick analysis shows it's not a vacuum leak. The 4-way held huge vacuum from yesterday when I popped off the line to the climate control. That would cover that line into the dash, but I tested it separately anyway. Then I put on Jeff's intake leak tester that fits on the MAF. WOW! TIGHT AS A DRUM. Thanks, Jeff!

The failure may be just due to very old gas and lack of driving. I emptied the tank and filled it with fresh 91, unfortunately AFTER the smog test, not expecting it to fail. I will contuinue down the list with a Spanner and Theo's Diagnositc test, spark plug analysis, injector check, new O2 sensor, MAF cleaning, some injector cleaner in the tank and maybe an intake track cleaning, compression check and cabon blowout. The MAF looks spotless and like shines new. This is one of those cars where the intake is still factory silver and has not turned tan from heat. All the rubber is new looking and very pliable. Nothing brittle or mushy from oil exposure. Oh, I should give the cam gears a quick Porken tool check too.

Onward.

John Speake

I do think the airpump trick will help.....

Bill Ball

John: You mean plugging the air pump so less air goes to the cat? That could raise HC but there is a lot of room there so it should still pass. In theory there should be no benefit since the air is injected after the NOX section except in the very early cars. Has this really helped later cars pass NOX? Is it more than plugging the vac line to the diverter?

Worth a try if it could help. I found a shop that is very inexpensive and allows a free retest.

John Speake

Hi Bill,
I have no diect experience of solving a NOX problem because only the very late 928s here in the UK had cats fitted, and there is no equivalent NOX etc. MOT test like the ones you have to pass in CA. We have a simple CO test at idle, plus a lambda test for cars first registered after 1994.

I appreciate that a lambda test is not the same as NOX, but lambda failed due to "weak" mixture. The problem for you is that I guess you can't test the car for NOX before you submit it ? If you can test then I'm saying that disconnecting the airpump blowoff vqalve vac feed is worth a try.

Good luck !

danglerb

Calif is still locked at 1975 and earlier, 1976 and newer actually face increasingly harder to pass smog checks.

danglerb

I suspect a dirty injector and a lean cylinder.

Bill Ball

All the spark plugs look the same. Here's one viewed from two angles. At first I read it as OK (tan deposit although lighter than usual), then lean. Slightly lean is bad enough. Also, the gaps were all about 40-45 thou. Supposed to be 28. These plugs are not old. Some crusty carbon on the outer ring - a bit of burned oil. I will pop in a new O2 sensor. The MAF is pristine. Sure might still be out of calibration. The gas was old. I put in fresh high octane. I'm going to try the smog test again with new O2 sensor, proper gapped plugs and fresh gas and see what happens.

heinrich

Spark plugs look perfect. Is that gap right?

<edit> OK read your words LOL ... I thought that gap looked way huge.

Bill Ball

Note the anitseize - they were a bitch to break free. I suspect they were overtorqued - that is torqued to 18-22 ft-lbs, which is usually correct, but too high with antiseize. Compression came in at 195 except for 3 cylinders were 205. Probably carbon'd up.

tveltman

Bill,

I skimmed this thread, so hopefully I didn't miss it, but I would advise against putting alcoholic fuels into the engine, since that just adds more oxygen, which will lean out the mixture further. Methanol in the tank should drop the HC numbers at the expense of NOx. Does CA check ignition timing? Seems like you could adjust the timing to cool down the combustion.