Often overlooked...dirty injectors
 

Hey heys, keep a long story short here but, I have a sweet 86GX that has a newer mazda installed engine, and she runs/ran so sweet. Problem is when the install happened (not me I scored her after the new block was put in) they re-used all the uppers from the old engine. No problem obviously as this is routine on a block swap...but...one thing they overlooked was cleaning or replacing the injectors. Needless to say 18 or so year old injectors tend (hehe) to be a bit clogged and dirty etc.

Why am I posting this common knowledge? Quite simply to remind everyone and to point out to new owners the importance of having clean freeflowing injectors. Many of the problems that I have read about on our forum and others can be totally related to having clogged dirty fuel injectors. And the nice thing about our car is that it is a relatively simple job (alright, a bit of a pain but) to pull the uppers off the engine and get these puppies cleaned or replaced.

I just did it this wekkend and was utterly amazed at how dirty and clogged they were. not to mention how bad the o rings grommets and caps were.

And as a tribute to how great the rotary is, I was amazed that my car ran at all and held a 750 idle etc with the condition that these FI's were in. What tipped me off to a problem on the way was simply the hot start flood situation. I knew everything on the engine was in great shape and decided to take a look at the injectors...good move.

Now I can actually FEEL the secondary injectors when they kick in at about 3600, a small rocket explosion goes off that was lacking.

So to sum up the short story (sorry)

*Consider looking into your fuel injectors when your engine is haveing gas related problems they are probably long overdue for cleaning or replacing*

This message brought to you by a rotary lover.

Terry

Did you have them professionally cleaned?

To answer your question it's not as common knowledge as you would think. I had mine cleaned as a matter of course.

Actually your right, it is not common knowledge, and actually why I posted this was to hopefully help solve a lot of owners problems, I worded it as common knowledge meaning to mechanics or good back yard mechanics but to many it is not known. Injectors are the most important piece of a FI system and are often overlooked to their maintence.

Well, it's common knowledge to me, I had my 550 primaries and my 850 secondaries sent to RC Engineering before I started reassembling my car. I was just asking if he did the same..

Cruzin Performance will clean them for half the price of RC and they have better service, and use the same equipment. $12/injector.

my car hardly ever starts when its hot could clogged injectors be the problem and sometimes when i rev it up to 7k and let it go back down it stalls sometimes and when i hard brake it could that simply be the only problem that makes it do this

Do they install new o-rings, grommets, and paint the injectors?

Yup exactly why I posted this thread, also the orings and grommets get cooked go hard and loose seal.

And another thing I encountered, the airbleeds can crack or break..

do they? i would also like to know.

I know RC does, but if they also do that, it would be an amazing deal and alot easier than ordering everything yourself. I'm personally getting tired of ordering parts whenever my 7 needs something..

Painted, new o-rings, grommets, and pintle caps. All for $12/injector.

www.cruzinperformance.com/fuelinj.html

excellent write up and photos of the cleaning process. The flow tests really underline the reason for me posting this in the first place. 2 of my injectors were so gummed up when I pulled them, I could hardly believe my engine even ran.

http://www.cruzinperformance.com/injsteps.html

again I hope this thread helps out some of your cars performance problems everyone.

Terry

yup - this is exactly the problem i'm having atm - the hot start flooding and such - most certainly clogged injectors - going to get them cleaned

They are a good shop.

does this mean those shitty fuel injector cleaner bottles that you are suppose to pour in with your tank of gas doesn't do shit?

i don't think they would help much.
i think you have to back flow them to get all the dir out?

Another possible suprise is that if you don't know your car's history, your engine may have the wrong injectors. When I had my injectors cleaned when the front rotor blew, I found that the two primaries were the wrong impedance (low vs. high). This was on a 1988 N/A.

can someone tell me how to take them out?
the manual doesn't say anything about it

Actually the factory shop manual covers it quite well, very easy to remove with their instructions...

http://www.fc3s.org left side ,how tos, manuals

or

http://www.iluvmyrx7.com manuals

My car is running perfectly now with no more hot start flood...finally!

I know I'm bringing this thread back from the dead but I'm thinking I will have to clean/replace my injectors...is it an easy job or should I take it somewhere? If I were to take it somewhere what would they charge about?

check the first page. $12/injector at that website.

is there a write up anywhere on removing injectors?

also would a fuel injector cleaning system work? like i called pep boys and they said it would cost 70 bucks and the car actually runs off the cleaning agent. i'm thinking it's probably not going to do a good job though.