Is there anyone that can check injectors?

O

oddiesGN

Member
Joined
Aug 23, 2009
Ok heres the deal, I had some 60# injectors with 1,800 miles and were only in the car for 6 maybe 7 months at most. I have had zero problems with them, never rich or injectors bleeding off. Well I wanted to upgrade to bigger ones so I sold them and now the person I sold them to is having problems. It idles good and is good when driving around, but when he get to 10# boost it cuts out. He did get a chip from TT for his set-up and he also says his fuel pressure on his gauge drops to zero as soon as he shuts it off. He is thinking that they are bleeding off from the injector. He also can't get the regulator to make fuel pressure go up or down.

I need to know if there is someone here in the community that could check them to make sure its not the injectors, because if they are bad for some reason I would have no problem returning his money or getting them redone if possible. Just don't know how good his mechanic is. I guess it took over 5 hours to do this, they were yanking on vaccum lines and even took off the regulator for some reason. And also when they installed the hotwire kit they never disconnect the battery because he told me that they kept getting sparks when they would touch the positive on alt to bare metal.

If anyone would know what would cause his problems please fill free to chim in or knows someone that could do a leak down test on these to see if they are bleeding out. Because like I said, I have no problems working with the guy just need to know whats going on since they worked great for me.

If you need to read his thread about this its "heater no workie" and its the fifth and sixth post in the thread.

Thanks, Otes.
 
A couple of years ago I had an air/fuel ratio issue I was trying to figure out and I had my 42.5 lbs injectors flow tested by Precision Turbo. They did a really good job and I was able to eliminate the injectors as a problem.
 
I would like to thank Eric at turbotweak, he said that he would check the injectors if the guy can't figue out the problem.

So with that out of the way, has anyone else had this problem or knows what would cause this?

Thanks, Otes.
 
oddiesGN said:
I would like to thank Eric at turbotweak, he said that he would check the injectors if the guy can't figue out the problem.

So with that out of the way, has anyone else had this problem or knows what would cause this?

Thanks, Otes.
Click to expand...

A description of what his problem is, might help with getting an answer....
 
Chuck Leeper said:
A description of what his problem is, might help with getting an answer....
Click to expand...

I thought I did in the first post and also said that he posted a thread "heater no workie" it was post #5 and #6 which he explains the problem.

As soon as his car turns off, fuel gauge drops to zero and it cuts out at around 10# of boost as if the up pipe came off. It idles good and drives good just at wot it pops and looses power. This is after installing 60# injectors from the stock one that he thought were bad.

I posted this thread to help him and me so I know whats going on too. He posted his problem on a different thread that had nothing to do with his fuel problem, it was about his heater so I made this one in hopes that more people will read this one with some help.

Otes.
 
If an injector was leaking down that fast there would be other issues Does the car misfire or smoke on start up? Sounds like the check valve fuel pump is bad. Did they do a pressure and volume test on fuel pump to verify if its doing its job. What does he have for a masairflow sensor? Was his car fine before injectors? Make sure regulator is not leaking fuel from vacuum port.
 
chopped39 said:
If an injector was leaking down that fast there would be other issues Does the car misfire or smoke on start up? Sounds like the check valve fuel pump is bad. Did they do a pressure and volume test on fuel pump to verify if its doing its job. What does he have for a masairflow sensor? Was his car fine before injectors? Make sure regulator is not leaking fuel from vacuum port.
Click to expand...

He has a translator on his mass air and he had to move the switches around to work with his new chip.
 
charlief1 said:
PM this guy, seriously.^^^^ I still need to send you a couple of injectors for your colection Chuck.:D Couldn't believe the truck ran on them either.:eek:
Click to expand...

I pm'd him earlier to comment on this so we can help him better.

Otes
 
Checked regulator no evidence of leaks no leakage around fuel return or under regulator. No leakage present on or around injectors?? Kirban style billet fuel regulator 6 months old, inline fuel rail gauge worked both up and down for the pressure. Does not work as of last night which I can't figure out? Stays only on 44 won't move down only up to 50 and down to 44 only? As soon as you turn the key off the pressure drops 30 then steadily down to 20 15 5 in about 30 to 45 seconds? I did have to change my translator settings at idle to lean at idle and 4% rich at WOT? Seemed to help alot runs great no knock only about 0.7 double checked everything and all seems good except for the dropping of pressure? Running a standard 3" LT1 MAF as well.
 
jretrodude said:
Checked regulator no evidence of leaks no leakage around fuel return or under regulator. No leakage present on or around injectors?? Kirban style billet fuel regulator 6 months old, inline fuel rail gauge worked both up and down for the pressure. Does not work as of last night which I can't figure out? Stays only on 44 won't move down only up to 50 and down to 44 only? As soon as you turn the key off the pressure drops 30 then steadily down to 20 15 5 in about 30 to 45 seconds? I did have to change my translator settings at idle to lean at idle and 4% rich at WOT? Seemed to help alot runs great no knock only about 0.7 double checked everything and all seems good except for the dropping of pressure? Running a standard 3" LT1 MAF as well.
Click to expand...

How is it now at wot? Is it still cutting out?

Otes.
 
jretrodude said:
Checked regulator no evidence of leaks no leakage around fuel return or under regulator. No leakage present on or around injectors?? Kirban style billet fuel regulator 6 months old, inline fuel rail gauge worked both up and down for the pressure. Does not work as of last night which I can't figure out? Stays only on 44 won't move down only up to 50 and down to 44 only? As soon as you turn the key off the pressure drops 30 then steadily down to 20 15 5 in about 30 to 45 seconds? I did have to change my translator settings at idle to lean at idle and 4% rich at WOT? Seemed to help alot runs great no knock only about 0.7 double checked everything and all seems good except for the dropping of pressure? Running a standard 3" LT1 MAF as well.
Click to expand...

My experience with the "mini" rail mtd gauges is mixed.
A. I checked many on the inj bench...Most were anywhere from 2 to 7psi "whacked". I did find tho, that once I found the inaccuracy, it held constant. I then made a reference chart for the customer.
B. The glycerin filled gauges have been reported to be inaccurate when subjected to under hood heat. [I have not seen/tested them to find out.]
C. Subjecting a gauge to engine vibration is not good for it's life span. I use hose connections only.

As for the gauge not going below 44#.. If the FP can't be turned below 44#, I'd look at:
A. The regulator.
B. The return line.
The adj reg should be able to have the set psi reduced by at least 5psi. If not, then look at A&B. [This, assuming the gauge is good.]

As for the fast psi drop @ engine shut down..As mentioned before, the injs would be hard pressed to drop that much fuel as fast as U R reporting. [
I'd think the drop is due to the pump check valve being fubar... Or, there's not 1 there.




Back under my rock....
 
Update! I changed the setting on the MAF translator to leaner at idle and 4% rich on WOT that made a hell of a difference where now I am not cutting out or starving the engine for fuel. Boost's up to 15 like it should with no cutting out, sputtering, popping etc. Wideband is telling me at idle (fully warmed up) 12.5 to 13.4 and not moving very much. With the stockers it would be at 14.6 to 14.8 with no changes to the translator. So it is still running rich. Called kirbans today talked to pete and he said if the regulator was bad the car would not start or it would have a misfire which is does not. He said to him it sounds like a leaky injector. He did say to that the 60's are running ALOT more pounds than the original stockers and the fuel line can only run so much fuel in it. He also said to that with having the 60's in there with all the pressure the regulator can't move down from 42-44 where it's at and can't go past about 50 on the high side. So sounds to me like the 60's are producing ALOT of pressure and the fuel line, regulator etc. is at it's max for pressure? If that makes sense? The fuel pump to is a walbro 255 LPH from precision installed back in july or august of 2011? Hope I can figure this out and hopefully which ever injector or injectors it is won't hurt the motor if it's washing down the cylinder(s). By the way don't see any black smoke coming from the tail pipes either or smell any gas from back there? And I did check and make sure the chip was in the computer the right way and checked the SES light to make sure it wasn't blinking or flashing a bunch of times. Let me know thanks again guys.
 
"So sounds to me like the 60's are producing ALOT of pressure and the fuel line, regulator etc. is at it's max for pressure? If that makes sense? The fuel pump to is a walbro 255 LPH from precision installed back in july or august of 2011? Hope I can figure this out and hopefully which ever injector or injectors it is won't hurt the motor if it's washing down the cylinder(s)."

The injectors have NO influence on the "PSI". A LARGE pump volume can over run the regulator. [If the reg is not designed to handle the flow, or is defective.]
As for the 60# injs being bigger than stockers and causing the issues...Nope.
As for the regulator being bad...could be.
The added flow created by the 255, will not over run the stock, return fuel lines, IF they are in good condition. [Check to see if they are kinked, the liner has let go, or there's a problem in the tank, the vent is plugged.] Take note of the rubber lines at the rear axle. Been lots of TR's going really fast w/ stock fuel lines.
 
I do have a low mile stock regulator that I'm going to try and see if the pressure still drops or not? If it doesn't then I'm getting another adjustable I suppose? Maybe some crap fell in the diaphram or something on the regulator? Causing problems? I'll let you all know once I do that
 
its not the injectors has he ever changed the fuel filter? the injectors were bad they would give problems way before 10psi it would smoke smell like gas it would have trouble starting etc... this guy changed his stock injectors because he thought they were bad why? what were the symptoms he had symptoms before he swapped out the stock inj.....it could be a bad fuel pump clogged fuel filter or their could be a problem with his injector harness or even might be a bad ground somewhere...
 
Wanted to upgrade to bigger injectors, fuel filter is only a year old if that, and all injectors are firing so it's not a bad harness. I'll let you know if it's the regulator or not. No symptoms before the swap?
 
As soon as his car turns off, fuel gauge drops to zero and it cuts out at around 10# of boost as if the up pipe came off. It idles good and drives good just at wot it pops and looses power. This is after installing 60# injectors from the stock one that he thought were bad.



this was the comment i was reffering to...i thought you had problems with the stock injectors...
 
the gauge shows FP drops to 0 when vehicle is turned off means the regulator is probably defective..or bad injector.. do you have a scanmaster what are your numbers on idle?? and the stock lines are fine ive seen my buddy run low 10's with stock lines, so tell "Pete" he needs to figure out what he's talking about...

try this when ignition ON Fuel pump delivering fuel what is your static FP does it stay @43 psi or does it fluctuate at idle?
 
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