Fuel Injector replacement (UPDATE)

Post by **pito11213** » Sat Dec 11, 2004 8:34 am

Well today I finally got to trying the injectors. As a reminder I have a 90 Q with injectors 1,3 and 6 ohming (please refer to Q45.org for ohming directions) bad.

Well I can say I have no fear off pulling the plenum now. It is alot of work but can be smooth.

First I do recommend thinking before you do as I waited till I took off the plenum bolts to realized I did not pull the fuel pump fuse and turn on the car the depressurize the fuel rail. As per a conversation with Wes I went the alternative route and opended the gas cap and pull the fuel line off after I pulled the fuse and cranked the motor about 8-10 times. Wes I did decide to pull both fuel lines though.

Then came disassemebly which is not that hard provided you have the necessary tools on hand. What would have come in handy was an angled screw driver (read on to find out why)

1. Removed plenum bolts and hoses that connected with the plenum that would have not allowed movement up and down or side to side freely. I then got a wood block and propped up the plenum. Well I didn't feel like taking off the EGR pipe or the EGR itself. The way the injectors are angled I could not get a screw driver on with enough leverage to turn the screws without damaging them so I stopped while I was ahead. The number 1 injector that I replace was a pain to get out of the rail. Once you get past that first O-ring it is a piece of cake. I personally decided to use dielectric grease on the O-rings to get them to slide in easy which worked like a charm. Make sure to tighten the screws and bolts without over doing it to prevent stripping or breaking the bolts.

Some helpful thing to have on hand1. Towels (plenty of towels just in case)2. Magnet stick. Something will be in a weird spot and dont risk trying to grab it.3. ANGLED SCREW DRIVERS.4. Wood block

I will post pics later and everyone should not be afraid to work on yourself. If I could do it in the parking lot at autozone you can do it too.

Post by **elwesso** » Sat Dec 11, 2004 8:46 am

Very good Pito... glad you got it done!!!!!

How does the car run now?

Post by **pito11213** » Sat Dec 11, 2004 12:00 pm

Well remeber I only changed one due to time costraints. The bounce is still there. I think bottome line I will just keep driving till I can get the other Q.

Post by **elwesso** » Sat Dec 11, 2004 12:46 pm

Probably hte more economical route... Maybe you should unplug that injector so that it will be closed, and not leak fuel...

Post by **Q451990** » Sat Dec 11, 2004 12:55 pm

Do you have a new Q lined up?

Heath

Post by **DAEDALUS** » Sat Dec 11, 2004 12:55 pm

A bad injector shouldn't leak fuel. If it's stuck open for any reason or if the seal is leaking unplugging it won't help. Better to have an injector that works halfway than one that doesn't do anything.

You go some big brass ones to fix cars in the parking lot like that. What if something unexpected comes up and you can't get her running right away?

Post by **pito11213** » Sat Dec 11, 2004 1:13 pm

First, Heath I think I do........You tell me.

D, I have been working on cars from my neon R/T to the current Q. If I cant get it working right away my mechanic is directyly across the street as insurance.

I replaced the first injector since that was the one that read open loop. I will ohm the injectors again tomorrow to double check.

Now I have two injectors that read below specs. So I should just leave those and wait or try to change another one?

Post by **Jesda** » Sat Dec 11, 2004 1:34 pm

Never seen an angled screwdriver. What about a short, stubby one?

Post by **DAEDALUS** » Sat Dec 11, 2004 2:53 pm

pito11213 wrote:D, I have been working on cars from my neon R/T to the current Q. If I cant get it working right away my mechanic is directyly across the street as insurance.

I replaced the first injector since that was the one that read open loop. I will ohm the injectors again tomorrow to double check.

Now I have two injectors that read below specs. So I should just leave those and wait or try to change another one?

That's cool. Little things pop up on me enough that I couldn't be so brave. No mechanic across the street, but Autozone is a bike's ride away if I need generic stuff.

I've seen several injectors that ohm higher than spec, one was at 48 ohms. With a stethoscope it sounded like they were still clicking away. Most likely not working as well as the others, but still opening. Another one I checked at over 200 ohms wasn't opening at all.

Post by **Q451990** » Sat Dec 11, 2004 8:41 pm

pito11213 wrote:First, Heath I think I do........You tell me.

Ohh... that Q

pito11213 wrote:I replaced the first injector since that was the one that read open loop. I will ohm the injectors again tomorrow to double check.

Now I have two injectors that read below specs. So I should just leave those and wait or try to change another one?

I've seen a screw driver head for a ratchet before... maybe that's it?

Just remember that on all of my injector failures - the associated spark plug was so badly fouled that it wouldn't spark. I had to clean or replace the plug before the miss would go away or even improve vs. the bad injector.

Heath

Post by **PoorManQ45** » Sun Dec 12, 2004 6:28 am

Jesda wrote:Never seen an angled screwdriver. What about a short, stubby one?

I have a few "angled" screwdrivers. They were straight to begin with. But then I beasted on them . Now I have "multi-purpose screwdrivers. It's amazing how often you need a screwdriver with a bent shaft(not talking about naughty stuff).

Good job Pito. I have worked on other cars in the Autozone parking lot before, but never on the Q.

Post by **aaronl** » Sun Dec 12, 2004 7:50 am

See the tool set in the photo. You can buy this at http://www.mytoolstore.com/chapman/chasmall.html

The set is available with metric hex drivers. These tools have helped me many times where it seemed nothing else would work.

Post by **pito11213** » Sun Dec 12, 2004 8:07 am

Well I have a ratchet screw driver attachment. But the problem is getting in there with enough torque to push down and not strip the scew while turning it. I could reach it but saw I was fighting a losing battle. Why oh why did they use screws to hold these down. Why not nuts like everywhere else on the motor. I would like to replace those screws with bolts. Doesnt make sense to have screws

Post by **JoshIsSciFi** » Sun Dec 12, 2004 8:45 am

the most work I've done in an auto zone parking lot was when I was living in DB, California and changed the spark plugs on my cavalier, took about 10 mins, and man, I've never EVER seen plugs that bad, neither have any of my friends, it melted through most of the plugs. Changed from Bosch +4s to Chapion Doubles immediately... big difference.

Post by **elwesso** » Sun Dec 12, 2004 9:06 am

Are you saying it ate the bosch plugs???

Fuel Injector replacement (UPDATE)

Fuel Injector replacement (UPDATE)

Re: Fuel Injector replacement (pito11213)

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Re: (pito11213)

Re: (pito11213)

Re: (Jesda)

Re: You need this

Re: (JoshIsSciFi)

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