Misfiring, where to buy injectors?

[xcm]

precision auto injectors either...


1) raised their prices in the last 6 months
or
2) charge less via ebay, im too lazy to check.

 

[gradon]

I agree with the heat soak issue. I haven't tried that BG44K yet, but know it's one of the best cleaners/treatments you can buy(certain things I get a "good feeling" about from reading and recommendations and this is one of them)

 

[orange]

Swap cylinders with the injectors to see if trouble moves.
Check fuel pressure.
Pull sparkplugs and check colors/condition.
Ground straps.
Weak Battery.

-------------------------
-What if the new '$300 parts' Do Not fix it??

Troubleshoot it First!

Good Luck,
Orange

 

[Wayne Sihler]

I replaced my plugs with champions three weeks ago.

I've researched heat soak numerous times on different forums. I went to the dealer to be sure the fixes were done to that jeep and they were. The heat shield looks stupid imo. I don't see how that would work much at all.

Jeep ride, I will take the injectors in to Napa. Does this flow bench test for leaking injectors or just the flow?

What Champion plug # did you use ?
They should be the double platinum ones at least.

Wayne

 

[muddeprived]

What Champion plug # did you use ?
They should be the double platinum ones at least.

Wayne

http://www.summitracing.com/parts/CPN-438/


Spark Plug, RC12ECC, Copper Plus, 14mm Thread, .750 in. Reach, Projected Tip, Resistor, Each

 

[muddeprived]

Swap cylinders with the injectors to see if trouble moves.
Check fuel pressure.
Pull sparkplugs and check colors/condition.
Ground straps.
Weak Battery.

-------------------------
-What if the new '$300 parts' Do Not fix it??

Troubleshoot it First!

Good Luck,
Orange

Does AZ or Advance sell a fuel pressure test tool? I don't have a tool to test the pressure and never seen one.

 

[McQue]

http://www.precisionautoinjectors.com/product.sc?productId=5&categoryId=2

I believe these are the ones we'd want for our 00-01 engines...someone please correct me if I'm wrong, because I'm about to buy a set!

Some info on INJECTORS, cut and paste from another thread...

Injectors *********

The following is a list of the injectors used on the 4.0L since 1987 along with their rated static flow:

Model Year, ...Part #, ......Colour, .....Fuel Pressure, ...Static Flow,
'87-'90, ........53003956, ...Dark Tan, ...39psi, .................18.6lb/hr
'91-'93, ........33007127, ...Brown, .......39psi, .................21.0lb/hr
'94-'95, ........53030343, ...Tan, ...........39psi, .................21.0lb/hr
'96-'99, ........53030778, ...Grey, .........49psi, .................23.2lb/hr
'99-'01, ........04854181, ...Blue tip, .....49psi, .................22.5lb/hr

The injector flow rate varies as the square root of the pressure drop across the injector. The stock '91-'95 4.0 injectors are rated at 22lb/hr @ 43psi fuel pressure, so at 39psi they flow ( sq. rt.(39/43) x 22.0 = 21.0 ).

For stock/modified 4.0 engines or stroker build-ups the following injectors can be installed. The flow rates are:

Ford Motorsport 19.0lb/hr @ 39psi (Part no. FMS-M9593-C302)
Ford Motorsport 24.0lb/hr @ 39psi (Part no. FMS-M9593-A302)
Ford Motorsport 30.0lb/hr @ 39psi (Part no. FMS-M9593-B302)
Chevy LT1 24.0lb/hr @ 43.5psi (Part no. 17124248)
Chevy LT4 28.0lb/hr @ 43.5psi (Part no. 17124251)
'98 Chevy LS1 25.2lb/hr @ 58.0psi (Part no. 12533952)
'99-'00 Chevy LS1 26.2lb/hr @ 58.0psi (Part no. 12456154)
'01-'02 Chevy LS1/LS6 28.6lb/hr @ 58.0psi (Part no. 12482704)
Accel 19lb/hr @ 43.5psi (ACC-150819)
Accel 24lb/hr @ 43.5psi (ACC-150824)
Accel 26lb/hr @ 43.5psi (ACC-150826)
Accel 30lb/hr @ 43.5psi (ACC-150830)

The '95 Jeep 5.2 ZJ/Dodge 5.9 injectors (Part no. 53030262) are rated to flow 24.6lb/hr at 39psi.

The selection of injector size will depend on the estimated horsepower output, brake specific fuel consumption BSFC (assume 0.5), no. of cylinders, and the injector duty cycle (assume 80% or 0.8). The formula is:

Injector size (lb/hr) = (horsepower x 0.5)/(no.of cylinders x 0.8)

 

[JNickel101]

That looks like a better deal if it's a set of 8. Can you verify that these work with our 00-01's?

Well, from the post/chart above, it looks like we'd want the Ford 19.0 lb/hr ones for our 00-01. Or the Accel 19.0s....or one of the Chevy's (didn't do the math yet).

I'm hoping someone else with an 00-01 who's actually done this will post up and say which one they're using - and results

 

[joe_peters]

Does AZ or Advance sell a fuel pressure test tool? I don't have a tool to test the pressure and never seen one.

Most chain auto parts stores now "rent" tools--you give them a security deposit, they refund it when you return the tool. While a FI pressure gauge is good to have, it is a tool you may not need for years at a time.

Did you give the hood trick a try?

 

[kastein]

Amusingly, AZ's rental/deposit prices are actually more than the tool is on the shelf (at least the steering wheel puller - $15 on the shelf, $20 to borrow.) I think they got tired of their carrying cases disappearing.

 

[muddeprived]

Some info on INJECTORS, cut and paste from another thread...

Injectors *********

The following is a list of the injectors used on the 4.0L since 1987 along with their rated static flow:

Model Year, ...Part #, ......Colour, .....Fuel Pressure, ...Static Flow,
'87-'90, ........53003956, ...Dark Tan, ...39psi, .................18.6lb/hr
'91-'93, ........33007127, ...Brown, .......39psi, .................21.0lb/hr
'94-'95, ........53030343, ...Tan, ...........39psi, .................21.0lb/hr
'96-'99, ........53030778, ...Grey, .........49psi, .................23.2lb/hr
'99-'01, ........04854181, ...Blue tip, .....49psi, .................22.5lb/hr

The injector flow rate varies as the square root of the pressure drop across the injector. The stock '91-'95 4.0 injectors are rated at 22lb/hr @ 43psi fuel pressure, so at 39psi they flow ( sq. rt.(39/43) x 22.0 = 21.0 ).

For stock/modified 4.0 engines or stroker build-ups the following injectors can be installed. The flow rates are:

Ford Motorsport 19.0lb/hr @ 39psi (Part no. FMS-M9593-C302)
Ford Motorsport 24.0lb/hr @ 39psi (Part no. FMS-M9593-A302)
Ford Motorsport 30.0lb/hr @ 39psi (Part no. FMS-M9593-B302)
Chevy LT1 24.0lb/hr @ 43.5psi (Part no. 17124248)
Chevy LT4 28.0lb/hr @ 43.5psi (Part no. 17124251)
'98 Chevy LS1 25.2lb/hr @ 58.0psi (Part no. 12533952)
'99-'00 Chevy LS1 26.2lb/hr @ 58.0psi (Part no. 12456154)
'01-'02 Chevy LS1/LS6 28.6lb/hr @ 58.0psi (Part no. 12482704)
Accel 19lb/hr @ 43.5psi (ACC-150819)
Accel 24lb/hr @ 43.5psi (ACC-150824)
Accel 26lb/hr @ 43.5psi (ACC-150826)
Accel 30lb/hr @ 43.5psi (ACC-150830)

The '95 Jeep 5.2 ZJ/Dodge 5.9 injectors (Part no. 53030262) are rated to flow 24.6lb/hr at 39psi.

The selection of injector size will depend on the estimated horsepower output, brake specific fuel consumption BSFC (assume 0.5), no. of cylinders, and the injector duty cycle (assume 80% or 0.8). The formula is:

Injector size (lb/hr) = (horsepower x 0.5)/(no.of cylinders x 0.8)

Awesome Info. I nominate this for post of the year!

Thanks!

 

[muddeprived]

Most chain auto parts stores now "rent" tools--you give them a security deposit, they refund it when you return the tool. While a FI pressure gauge is good to have, it is a tool you may not need for years at a time.

Did you give the hood trick a try?

Not yet. It hasn't misfired since I returned from the trails. I haven't driven it long distances yet so....

 

[joe_peters]

Not yet. It hasn't misfired since I returned from the trails. I haven't driven it long distances yet so....

Ok, sent you a PM on some parts.

 

[JNickel101]

Joe, I noticed you're running the 19# injectors....any reason why these wouldn't work for a 2000-01?

 

[gradon]

The 99+, 2000, and 2001 have different injector harnesses--ev6--that won't work with any of the above except the ls1s and maybe the accels(might have to search for some different accels than the above). When Jeep went to the newer style manifold, they changed the injectors and harnesses. Now you can buy adapters so that you can use the ev1 injectors(or cut and solder the ev1 connectors in), but it's probably better to source an ev6 injector that will flow 22.5#(or a tad more if you have some breathing mods) on your 49psi rail. ev6 injectors are skinnier than the older ev1s(maybe a bit longer too). The ev info should be added to the above list to make it completely helpful.

 

[JNickel101]

You're awesome - thanks so much for that info!!!

I can't seem to find any info on connector types anywhere...so I emailed 5.0Motorsports about their different injectors. I'm hoping that:

Bosch 21lb - NEW
"Yellow Tops"
0280155710

will work, but I can't tell from the pic if they are EV6 connectors.

 

[joe_peters]

gradon is right on the money.

There are adaptors available to go EV1/EV6, here is a link:

http://www.fiveomotorsport.com/Injector_CONNECT.asp

I would really do my homework before trying any mods with an OBDII vehicle. Renix and OBDI will let you get away with a whole lot more than OBDII.

 

[97lilgrnxj]

+1 for fiveomotorsports....running there 27# bosch injectores in my stroker...love em good price, quick shipping

 

[97lilgrnxj]

give the guys at fivomotorsports a call, tell them what you have and he will tell you exactly what you need!

 

[muddeprived]

Ok here's an update. I installed the new injectors, new plugs, and a new coil rail. It's still misfiring. :dunno:

It seems to misfire after i take it on the highway or push it a little hard (drive fast and accelerate fast). I keep getting various misfire codes from multiple cylinders, sometimes just cyl 3, somtimes 3 or 4 cylinders at once.


What should i check next?