Which injectors?

[HMeeder]

I have always suspected my car of running rich (PO said that it wouldn't pass smog here in CA. It's a '72 so that is no longer an issue.) The car has always had a slight 'stumble' running at constant RPMs, though it accelerates just great. I've gone through everything in the FI (cleaned injectors, double checked the fuel pump pressure @ 29 PSI, new filter, all grounds are solid, trigger points are good, timing dead on and all vacuum hoses new and tight.) So here's the thing:

I finally carefully read the manuals I have and they state that a 1.7 should have yellow injectors. My injectors are beige (from a 1.8. The PO was a parts yard scavenging fool.) How large a factor would the incorrect injectors be? Could they be contributing to the 'stumble' ? (barely noticeable, If my ass wasn't connected to the car so intimately I couldn't tell.)

I pretty sure that would be why the car wouldn't pass smog, but I'm not going to spend the $$ for a test I don't need.

Mostly just curious. I'm sure not going to spend $300 for a new set of injectors, and the car runs strong at AutoX (maybe I have a secret weapon!)

Is there anything I should do to counteract this running condition? and is there any conceivable way it could harm the motor?

Many TIA!

[Dave at Pelican Parts]

Beige could be a faded/oily yellow. Check the part numbers to make sure--I think they're on or under the electrical connector.

The wrong fuel injectors may very well change your mixture. Some sources have claimed that mixing D-jet and L-jet injectors will fry either them or the ECU, but I'm finding that a bit hard to credit with the voltage and current that people have measured going to the injectors of D- and L-jet 914s.

How do the spark plugs look? If they're black and fluffy, you're definitely running rich.

Cruise stumble is the classic bad throttle switch stumble.

--DD

[HMeeder]

My wife states that the injectors are 'almond' not beige (she gave me a look like I'm an idiot for not knowing the difference.)

At any rate, she agrees that they are not now nor ever have been yellow. The only markings are the word 'PYTHON' next to the connector, a 2 or 3 in the tip of the injector, and the number 188 scratched with a Dremel or the like on the fuel line end (or 881 if looked at the other way 'round.)

So, my assumption is that they are 1.8l injectors. I believe that I am going to just leave things as they are (I wonder if having the wrong injectors constitutes a modification of the FI as regards PCA AutoX classification? I'll have to read the rule book carefully to see.)

The plug tips are dusty whitish-brown (or perhaps 'almond') so being too rich doesn't appear to be a factor.

I have pulled apart the TPS and the copper circuits printed on the board are getting thin. I have a replacement on my current wish list as I had suspected it of the constant running problem.

Since I apparently do have the higher volume injectors, is there anything I should do to ensure a good clean burn? It seems that everything else is just fine.