Home
Don't have an account? Create one now! It's always free!


Forgot Password
Ed's Auto Parts - Mention MOTORGEN for a Discount!
Motorgen Sponsor: McLeod Racing
Motorgen Sponsor: American Muscle - Add style and performance to your Stang
Motorgen Sponsor: Hall Fabrication & Racing
Motorgen Sponsor: Injectors Plus - Performance Fuel Delivery Systems
Reply
 
Thread Tools
Old 01-09-2010, 04:05 PM   #1
DamianDamian is offline
Senior Member
 
Damian's Avatar
 
Join Date: Jun 2009
Posts: 2,509
Default injector help

Im getting a misfire code, and Im having problems diagnosing the problem. Ive checked everything from the plug to the distributor and those are all good. The cat is good as well. The only other thing I can think of is the injector. How can I check it to see if its bad, going bad, or anything? Do I check resistance, voltage??

Also, I only throw the code if Im really pushing the car hard at high speeds, and I can feel it misfiring. Its only on cylinder #2, no other codes at all. This is an OEM injector in an Eclipse out of a Diamante. The Diamante has 275cc injectors, the Eclipse has 22cc injectors. The injectors are properly scaled and tuned for.

Thanks in advance.
__________________
93 GMC Typhoon: new money pit/PITA. Now GT3788R powered.

Boost, because sometimes atmospheric pressure just isn't enough.

"If it has tit's or tires, you can be pretty sure your going to have problems with them..."
  Reply With Quote
Old 01-09-2010, 07:34 PM   #2
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

Quote:
Originally Posted by Damian View Post
Im getting a misfire code, and Im having problems diagnosing the problem. Ive checked everything from the plug to the distributor and those are all good. The cat is good as well. The only other thing I can think of is the injector. How can I check it to see if its bad, going bad, or anything? Do I check resistance, voltage??

Also, I only throw the code if Im really pushing the car hard at high speeds, and I can feel it misfiring. Its only on cylinder #2, no other codes at all. This is an OEM injector in an Eclipse out of a Diamante. The Diamante has 275cc injectors, the Eclipse has 22cc injectors. The injectors are properly scaled and tuned for.

Thanks in advance.
Swap the misfiring cylinder injector to another cylinder and see if the misfire code follows the suspicious injector.

How many miles on the injectors? Did it ever sit for a long time? It might just have a little residue in the injector. Sometimes just running a can of Sea Foam with a tank of gas can be enough clean out injectors.

You ca also PM jsup of InjectorsPlus, he may be able to give you a technical test procedure.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 01-09-2010, 11:33 PM   #3
DamianDamian is offline
Senior Member
 
Damian's Avatar
 
Join Date: Jun 2009
Posts: 2,509
Default

I was hoping I didnt have to swap the injectors around since everything is such a tight fit. It sits for maybe 1 week tops, and Im not sure how many miles are on the injectors, but they are used.

The weird thing is though is I dont get any misfiring at normal driving, or even punching it on the on ramp. I only throw the code if I smash it at high speed on the freeway.
__________________
93 GMC Typhoon: new money pit/PITA. Now GT3788R powered.

Boost, because sometimes atmospheric pressure just isn't enough.

"If it has tit's or tires, you can be pretty sure your going to have problems with them..."
  Reply With Quote
Old 01-09-2010, 11:54 PM   #4
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

Quote:
Originally Posted by Damian View Post
I was hoping I didnt have to swap the injectors around since everything is such a tight fit. It sits for maybe 1 week tops, and Im not sure how many miles are on the injectors, but they are used.

The weird thing is though is I dont get any misfiring at normal driving, or even punching it on the on ramp. I only throw the code if I smash it at high speed on the freeway.

I'm not an expert on this, only making a kind of guess. The difference in these cases is that while you are at high speed (revs) you are also at a higher point in the duty cycle and *maybe* it's getting fatigued/hot and cuts out you stomp on it from there.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 01-10-2010, 03:05 AM   #5
DamianDamian is offline
Senior Member
 
Damian's Avatar
 
Join Date: Jun 2009
Posts: 2,509
Default

That was my thought, but at that rpms and throttle position, the ECU load is relatively the same, regardless of speed. Thats why this is such a pain in a$$ pinning down the problem. Ill pull the injector out later and inspect it, and swap it around with another one and see if the problem follows it. If it doesnt, seafoam it is. If it does, Ill get another injector.


Heres another question, if the injector is bad or faulty, wouldnt I get an injector related code along with a misfire code? I would think so, but I could be wrong.
__________________
93 GMC Typhoon: new money pit/PITA. Now GT3788R powered.

Boost, because sometimes atmospheric pressure just isn't enough.

"If it has tit's or tires, you can be pretty sure your going to have problems with them..."
  Reply With Quote
Old 01-10-2010, 03:10 AM   #6
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

Quote:
Originally Posted by Damian View Post
. . . Heres another question, if the injector is bad or faulty, wouldnt I get an injector related code along with a misfire code? I would think so, but I could be wrong.
Again, not an expert. However, I have an ODBII car that had a misfiring problem related to an injector that was intermittently working. There was no code at all, because the misfires were within tolerance apparently.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 01-10-2010, 03:13 AM   #7
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

DISCLOSURE: InectorsPlus is a paying sponsor of the site.

jsup may be able to help you test the injectors and provide a report. They can certainly rebuild your set (if they're rebuildable), or sell you a new set of flow matched injectors. BRIAN was pleased with the set he got for his Supra.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 01-11-2010, 03:04 AM   #8
DamianDamian is offline
Senior Member
 
Damian's Avatar
 
Join Date: Jun 2009
Posts: 2,509
Default

I sent him a pm.
__________________
93 GMC Typhoon: new money pit/PITA. Now GT3788R powered.

Boost, because sometimes atmospheric pressure just isn't enough.

"If it has tit's or tires, you can be pretty sure your going to have problems with them..."
  Reply With Quote
Old 01-12-2010, 05:24 AM   #9
DamianDamian is offline
Senior Member
 
Damian's Avatar
 
Join Date: Jun 2009
Posts: 2,509
Default

Well, I figured out the problem. It was injector related, but not the actual injector. The rubber seat that the injector sits in somehow cracked off a small piece of rubber and was sucking in air. So once I get a new one, the car should run quite a bit better too.
__________________
93 GMC Typhoon: new money pit/PITA. Now GT3788R powered.

Boost, because sometimes atmospheric pressure just isn't enough.

"If it has tit's or tires, you can be pretty sure your going to have problems with them..."
  Reply With Quote
Old 03-09-2010, 05:56 PM   #10
jsupjsup is offline
Site Sponsor
InjectorsPlus
 
Join Date: Feb 2009
Posts: 208
Default

Check for a bad ground. Seriously.... It's a real PIA but I suspect could be the culprit.
  Reply With Quote
Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -7. The time now is 04:19 PM.