Failed emissions test '86 Spider

[borrani]

Hey All,

CarPoor came over this morning in his newly purchased '90 Spider, and said 'hey, let's go get our new Spiders emission tested'. I said fine.

Just last week I fastened the lovely redone head to the car and she fired up just fine, and drove nicely as well. First time driving the car since I bought it two months ago.

She really does run well, but the idle is uneven and rough, not tickover smooth. I did replace the 4 intake manifold rubbers, and anything else that looked leak-prone.

She failed HC at idle. Limit was 220, i was 280. I'm not terribly surprised, as when the idle occasionally misses like that, it's got to blow the test.

Here are all the no.s. 1st number is my car, 2nd number is the limit.

Cruise HC 118/160 limit pass
Idle HC 280/220 limit fail

cruise CO 0.65%/1.2% limit pass
idle CO 0.03%/1.2% limit pass

I'll talk to my usual pros early next week, but I would greatly appreciate any tips on solving my slightly rough idle and idle HC failure. Also, I did adjust the idle just beforehand, and perhaps got it a little too low. It was idling at 880rpm or so, it's happier closer to 1000rpm. Idle limit for testing is 1200rpm, it's quite possible it'll pass with that little change as the idle is more even.

Thanks in advance,

Steve S.
Seattle, WA

[Sniady]

do you have 02 readins, nox? even co2?

[gotglasses]

I failed yesterday in New York, also for HC. I had several threads about my fouled dark plug color on my 86.

My problem was that the AFM was tinkered with and I went into the test with the idle mixture too lean ( thinking I'd better lean it out for the test, idle was around 900RPM, but chugging when I left station ). A lean mixture will cause misfire and high HC. Go to

http://www.oldebottles.com/italiancarspage3.htm

and see how he adjusts idle mixture and full throttle using a VOM.

At idle this is a bit tricky, but it did improve my situation. Passed today in different station ( which may have been my problem since I was only off a bit .91 vs .81 gpm limit) New Bosch Platinims also helped. Also , don't let them idle car for twenty minutes while they perform safety inspection. Idle should be higher mine was over 1100 after I adjusted idle mixture to get the .45volt average reading. Plugs now look less fouled, still not great, but good till next year at little cost.

[CarPoor]

Borrani left out the funniest part of this little scenario...we both have Spiders that are new to us and need to be emissions tested, so we were trying to figure out our game plan for the day. After some debate, I turned to Steve and said "Let's go get tested!" and it was pretty funny, like a gay couple going down to the clinic! Then on our way there, a cutie in a Brown Grad gave Steve a honk and said "Nice car!" All three of us were cruising in Spider Grads with the tops down. One Brown, on red, one black.

[Greg Gordon]

Borrani: Your cars numbers at cruise are so low that this almost has to be an adjustment problem. Use the information on the link to the oldebottles page (thanks gotglasses!) to set your idle speed. Set timing exactly. Then adjust your AFM idle mixture. It is a little tricky, the hotter the O2 sensor the easier it is. This is the most accurate way to set mixture without really expensive equipment.
It's possible an Aux Air Device that doesn't close all the way can screw up the idle emissions. To eliminate any possibility of this during the test I suggest you plug it so no air can go through it, then put the hose back on so it looks normal. If that effects the idle speed then adjust it back to factory specs and go take the test. Just remember to unplug the thing later or it will not start very well when cold.

Greg Gordon http:www.oldebottles.com
82 GTV6 85 GTV6 75 Fiat 128 66 Fiat 600 64 Ford 500 Truck 03 Buick Le Sabre GT(family car)

[borrani]

Hi All,

Many thanks for the advice, it definitely gives me something to go on.

How do I set timing? I set the distributor to its static mark when putting the head back on, and the cams are on their marks, but I thought the ECU did the actual timing of the motor. Rotating the distributor doesn't get me a thing, I thought. I'm new to this L-Jet stuff, but happily learning. Well, i remember the idle spec as 11deg BTDC, so perhaps I'd better check that and try the disty thing. I have a dial-back timing light.

My tach was reading a tad low, so if I raise the idle to a true 1000rpm, it should idle better, too, but you're saying it looks like I do need an adjustment, that's cool.

She starts cold just fine, then settles down to a too-low rpm and eventually dies after about 30sec. I would imagine I may rectify all of this with a properly tuned motor.

She actually runs and drives just fine, but after driving Pat's newly purchased '90 Motronic spider, it's night and day! The motronic cars truly get up and scoot, no question about that. They breathe!

Sorry Sniady, no other numbers to give you, I was just reading the inspection report.

Thanks for the advice,

Steve S.

[Greg Gordon]

As far as I know rotating the distributor adjusts timing on all L-Jetronic cars. Motronic is different.

The settling down to a too low RPM and eventually quiting is a sign of an air leak but it could just be that the idle is way out of adjustment. Properly set up the L-Jet car is very nearly as quick as the Motronic car.
Greg Gordon www.oldebottles.com

[borrani]

Hi Greg,

Great stuff. Usually I check the timing at full advance, but I'll check the idle's timing spec as well.

In your wonderful website, you mention to disconnect the coolant temp to ignition retard sensor. I'm certainly game to do this, and I'll check out my '86 Spider to see if it's got one. From what you know, did the Spiders come with this? When I had the head off, I counted 3, maybe 4 sensors sticking into the water jacket of the intake manifold. I took a picture of it just for fun. Amazing.

I took off the fuel rail, and inspected all the injector's gaskets, and they really seemed healthy. I did replace all 4 of the plenum to intake manifold donuts, just to make sure.

I'll get out the ohmmeter and go to town on it later this week or weekend, with your notes close in hand.

The too-low idle thing is cold start only. Once it's warm, she'll idle all day long in hot temps at 180F, gotta love that cleaned out radiator and new shroud. The hot idle is a bit lumpy, with the occasional miss, but that's exactly the issue we're addressing here. Oh yes, I'll remove and clean out my Auxillary Air Valve as well, great advice.

Thanks again,

Steve S.
Seattle, WA

[Greg Gordon]

Off hand I don't know if the Spider has the coolant temp to igntion retard device. If it does it should be eliminated. A too slow idle when cold could be the Aux Air Valve not opening enough. A faulty or mis adjusted throttle position switch could cause all these problems too.
Greg Gordon

[gotglasses]

I had the same problem with the stall after 30 seconds - you are too lean and are running on the cold start gas till it turns off. Your HC will be high. After I richened my idle mixture the problem went away and it does not stall,even with A/C on.

I agree that Spiders are diff than GTV-6 , you cannot accomplish anything by moving distributor off it's index mark. Timing set by computer , we have two - one for Fuel and one as large mounted vertically on right side for ignition. Just check it , it will be 11 deg .at the proper speed.

Try to borrow an RMS VOM so you can average readings directly on the readout, beats following the bouncing readings.

[borrani]

I'm going to adjust the CO tonight. There are 3 wires coming up from the 02 sensor. One of them has its own connector, then there are two that are shared. Which wire do I attach my voltmeter to?

The port where I adjust the idle CO is plugged, but the previous owner has nearly drilled a hole through the plug, but it's near the edge of the plug. Very strange. I could finish drilling through his hole, then hope I can pull the plug off, or ? Any favorite methods of pulling that plug, and resealing it?

Mille Grazie!

Steve S.
'86 Grad
'65 GTA - no emissions devices

[Greg Gordon]

Hi Borrani,
Measure voltage from the wire that has its own connection. The two wires that are together and use a Bosch type connector are NOT the ones you use.
It's typical to drill a small hole near the edge. Stick something small in there and twist the cap out, there is probably no need to drill a larger hole. Just put the same cap back in, no need to go through a lot of trouble to seal it.
Greg Gordon

[borrani]

I just love this Alfabb!!! Thanks, Greg et al.

I did try rotating the plug out, but it doesn't appear to be threaded. In fact, I can see what looks like a locking ring in there. I really did fiddle with it for quite a while, but could never really work it out. I'll fiddle s'more in about 90 more minutes when I'm home.

ss

[Greg Gordon]

It's not threaded. The twist method just helps if it's stuck. Drill a bigger hole if you need too.
Greg Gordon