Secondary ports dirty
10-31-2016, 09:20 PM
#1
Instructor
Thread Starter
Secondary ports dirty
Was doing some work under the plenum and noticed that the injector housings' secondary intake ports were dirty, before the secondary port valves. The primary ports were much cleaner, almost spotless. My secondaries open just fine when using my scan tool and the vacuum system is tight. Anyone know if this is normal and what is going on here? The primary intake ports are forward to the secondaries, right? Thanks.
11-01-2016, 01:03 AM
#3
Safety Car
Its normal. Its also one reason I tossed that entire system right out. If youre not wot far too often, youre getting carbon build up and deposits on the entire secondary runner, valve, injectors etc etc. I took my plenum off and looked down mine recently and sure enough both were super clean 
11-01-2016, 10:19 AM
#4
NCM Lifetime # 982
These engines run better and cleaner when exercised very regularly.
Plus if the car is a 90-92 there may be injector problems starting to surface. Not a big deal just get a set of good injectors.
When in doubt re-read the first sentence.
Plus if the car is a 90-92 there may be injector problems starting to surface. Not a big deal just get a set of good injectors.
When in doubt re-read the first sentence.
11-01-2016, 08:20 PM
#5
Instructor
Thread Starter
It has new injectors. Thinking of getting the tune to run the secondaries all the time. Just need to get some money together, I think it is like $500 for the tune. Thanks everyone!
11-02-2016, 09:45 AM
#6
Le Mans Master
Member Since: Oct 2004
Location: South-central Missouri
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Mark Haibeck provided my secondary delete-option prom, and with it he boosted the rev limit to 7600 (I was hitting the limiter in 3rd gear when running the quarter mile), and he changed the fan control so that both fans come on at 205ºF and shut off at 200ºF
I love the secondary delete function, and would never go back. Just too many +'s and NO -'s!
If your motor is not ported, the secondaries are easily recognized (with the plenum off) by the fact they are larger than the (dirty) primary runners.
11-11-2016, 07:54 PM
#7
Instructor
Thread Starter
11-13-2016, 12:27 PM
#8
Drifting
I've seen secondaries so gunk'd up that you couldn't force them open manually. No way they would have been operable with the secondary port throttle system.
11-14-2016, 07:52 AM
#10
Le Mans Master
I'm pretty happy with the secondaries deleted and as they say "parts left off don't weigh much or break"
if you are concerned you can wire them open and use the correct secondary delete chip and I believe you'll really like the results.
if you are concerned you can wire them open and use the correct secondary delete chip and I believe you'll really like the results.