Post injector-install woes!
Thread Starter
Instructor
Joined: Nov 2003
Posts: 102
Likes: 0
From: Fountain Valley CA
Post injector-install woes!
Finished up putting everything back after replacing injectors. While I was at it, I replaced the water pump; pulled, cleaned, painted my valve covers; also bead-blasted the TPI setup and intake manifold. The injector job turned out good; no leaks.
The bad: The car will not start and idle with the MAF and IAC connected. The IAC (Standard brand) is new and adjusted according to the shop manual. I also have only 10" vacuum; I can hear the leak but can't trace it to a particular area. All gaskets are new GM.
I anticipated having problems so I bought an AutoXray EZ Link scanner, but it was no help; kept getting "Vehicle is not responding" messages. After talking to AutoXray tech people, they say that their unit is not compatable, particularly with my '89 because of the ECM. Go figure.
Any help/tips to get my Vette back and running would be appreciated.
Thanks, guys.
The bad: The car will not start and idle with the MAF and IAC connected. The IAC (Standard brand) is new and adjusted according to the shop manual. I also have only 10" vacuum; I can hear the leak but can't trace it to a particular area. All gaskets are new GM.
I anticipated having problems so I bought an AutoXray EZ Link scanner, but it was no help; kept getting "Vehicle is not responding" messages. After talking to AutoXray tech people, they say that their unit is not compatable, particularly with my '89 because of the ECM. Go figure.
Any help/tips to get my Vette back and running would be appreciated.
Thanks, guys.
Racer
Joined: Apr 2003
Posts: 371
Likes: 0
From: Kingsport TN
Re: Post injector-install woes! (89C4)
Been fighting a problem like yours. Was told to use a propane torch to seek out leak. Engine rpms will flare up when you find it. Was going to try it my selt but my torch was empty. got to get a new cyl. Good luck. :thumbs: :seeya
Safety Car
Joined: May 2003
Posts: 3,789
Likes: 0
From: [Quote=WOEII] Is dried brown doodie powders man! [/Quote]
Re: Post injector-install woes! (89C4)
Purely out of curiosity, how loud is the leak? A common overlooked source of vacuum leaks (just did this myself) is under the throttle body. There is a tiny vacuum feed under the TB that I believe is for the EGR (i am not sure on that though). It is certainly worth a look.
:cheers:
:cheers:
Thread Starter
Instructor
Joined: Nov 2003
Posts: 102
Likes: 0
From: Fountain Valley CA
Re: Post injector-install woes! (89C4)
Also, getting Code 33 and some backfiring through the intake. Probably damaged my MAF. Ouch!
I'm pretty sure I got all the vacuum connections: one under the plenum by the TB; two at the rear, passenger side; and the brake booster.
It's a loud hissing noise; I only heard it after I got the car started and idling after disconnecting the MAF. If I leave the IAC connected, the idle will start to hunt and speed up some to around 2000 rpm.
[Modified by 89C4, 9:05 AM 4/13/2004]
I'm pretty sure I got all the vacuum connections: one under the plenum by the TB; two at the rear, passenger side; and the brake booster.
It's a loud hissing noise; I only heard it after I got the car started and idling after disconnecting the MAF. If I leave the IAC connected, the idle will start to hunt and speed up some to around 2000 rpm.
[Modified by 89C4, 9:05 AM 4/13/2004]
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Post injector-install woes! (89C4)
It is definitely a vacuum leak; recheck all vacuum lines:
-two on the right side of the TB
-one under the TB
-two on right rear of plenum
-brake boodster on left rear of plenum (uhuh)
Are you sure your AutoXray is properly configured by year & vin letter? My old unit works on my '88 and newer; if you can't get it working on your '89, demand a refund from them or a replacement with the proper unit.
[Modified by 65Z01, 12:17 PM 4/13/2004]
-two on the right side of the TB
-one under the TB
-two on right rear of plenum
-brake boodster on left rear of plenum (uhuh)
Are you sure your AutoXray is properly configured by year & vin letter? My old unit works on my '88 and newer; if you can't get it working on your '89, demand a refund from them or a replacement with the proper unit.
[Modified by 65Z01, 12:17 PM 4/13/2004]
Safety Car
Joined: May 2003
Posts: 3,789
Likes: 0
From: [Quote=WOEII] Is dried brown doodie powders man! [/Quote]
Re: Post injector-install woes! (89C4)
I am having an almost identical issue. Our cars are slightly different though. I just did a cam swap, head R&R and single plane EFI install. Start the car, immediately goes to 2000 RPM, whistles like a freight train for a few seconds and dies. I am talking a very loud whistling that can be heard over open headers :crazy:
Two things I see in common:
I am assuming you removed the TB for the bead blast. Did you buy a new gasket or re-use the old one? I ended up buying new with no change.
I also removed my injectors. Had sealing issues in the fuel rail (custom rail) but new upper o-rings fixed that. I did not replace the lower o-rings and it says directly in the service manual that they are to be removed and replaced any time you remove your injectors. That is next on my list.
Here is a linky to my thread:
http://forums.corvetteforum.com/zerothread?id=796728
:lurk:
Two things I see in common:
I am assuming you removed the TB for the bead blast. Did you buy a new gasket or re-use the old one? I ended up buying new with no change.
I also removed my injectors. Had sealing issues in the fuel rail (custom rail) but new upper o-rings fixed that. I did not replace the lower o-rings and it says directly in the service manual that they are to be removed and replaced any time you remove your injectors. That is next on my list.
Here is a linky to my thread:
http://forums.corvetteforum.com/zerothread?id=796728
:lurk:
Thread Starter
Instructor
Joined: Nov 2003
Posts: 102
Likes: 0
From: Fountain Valley CA
Re: Post injector-install woes! (Upstate)
Hey Upstate,
Yep, installed all new gaskets(GM). The injectors(FiveOMotorsports) came with both O-rings. You know, come to think of it, the "wind" seems to come from the area around the injectors on the rear driver side.
Thanks for your input.
Yep, installed all new gaskets(GM). The injectors(FiveOMotorsports) came with both O-rings. You know, come to think of it, the "wind" seems to come from the area around the injectors on the rear driver side.
Thanks for your input.
Burning Brakes
Joined: Nov 2003
Posts: 844
Likes: 0
From: Cape Cod Ma
Re: Post injector-install woes! (89C4)
OOHHHH Yaa my car among other forum members are having the same troubles. I have pinpointed mine to the o-ring seals on the injectors. After spending 40+ hours on hunting the problem down. Cant be anything else.
:beatdeadhorse:
:beatdeadhorse:
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Thread Starter
Instructor
Joined: Nov 2003
Posts: 102
Likes: 0
From: Fountain Valley CA
Re: Post injector-install woes! (redfast)
You're right, Redfast.
I just confirmed my vacuum leak by spraying carb cleaner around the base of the injectors; idle increases along with vacuum. I'm going to remove the retaining rings so that they'll seat lower into the manifold and see what happens.
I just confirmed my vacuum leak by spraying carb cleaner around the base of the injectors; idle increases along with vacuum. I'm going to remove the retaining rings so that they'll seat lower into the manifold and see what happens.
Racer
Joined: Apr 2003
Posts: 371
Likes: 0
From: Kingsport TN
Re: Post injector-install woes! (redfast)
Bought my o-rings today. Remembered one side os the fuel rail pulling out and I just pushed it back in. They say you can't do that :eek: So for $10.00 and some more time I figured what the heck. They are 15 years old. Hope it works. :seeya