Randy in Maine

When my fuel injectors come back they supply a testing document that indicates the before and after cleaning testing they perfomred. This one is off a buddy's 78 VW bus with a bad O ring on injectors #4 using 25 year old factory Bosch injectors. His bus sat for a number of years and in the air cooled VWs they tend to get munged up pretty at the tips and in the spray pattern due to the high cylinder head temperatures they run. His were not really very bad, but you do not know until you see the numbers. Calibration is probably the wrong term but th eide is for them to spray well and flow about the same rate after cleaning. Test pressure = 43.5 psi Test 1. Injector Resistance #1=2.5 #2=2.5#3=2.6 #4=2.5 Test 2. Leak Down Test (Pass / Fail) #1=P #2=P #3=P #4F <- o-ring failure Test 3. Spray Pattern (Good / Fair / Poor) #1=F #2=F #3=F #4F Test 4. 90 Second Pulsed Flow Delivery (mL) #1=76 #2=75 #3=77 #4=75 Test 5. 100mL Pulsed Volume #1=99 #2=98 #3=100 #4=97 Test 6. 20 Second Static Flow (mL) #1=74 #2=74 #3=76 #4=74 Test 7. 100mL Static Flow #1=97 #2=97 #3=100 #4=97 Test 8a. Injector Coil Test - On #1=5.9 #2=5.89 #3=6.01 #4=5.95 Test 8b. Injector Coil Test - Off #1=6.2 #2=6.19 #3=6.32 #4=6.24 Test Results After Service -------------------------- Test pressure = 43.5 psi Test 1. Leak Down Test (Pass / Fail) #1=P #2=P #3=P #4=P Test 2. Spray Pattern (Good / Fair / Poor) #1=G #2=G #3=G #4=G Test 3. 90 Second Pulsed Flow Delivery (mL) #1=79 #2=77.5 #3=78 #4=78 Test 4. 100mL Pulsed Volume #1=100 #2=98 #3=99 #4=99 Test 5. 20 Second Static Flow (mL) #1=75.5 #2=75.5 #3=76 #4=75.5 Test 6. 100mL Static Flow #1=99 #2=99 #3=100 #4=99 Approximate pound-per-hour flow #1=19.37 #2=19.37 #3=19.5 #4=19.37 I would certainly consider using those Ford 19 pounds injectors if they were pretty well documented what the flow rates are. Signs to look for seal leakage include obvious dripping on the outside, fouled plugs, poor mileage, inability to maintain adequate residual fuel pressure in the fuel rail, a vacuum leak at the leak, adn poor starting/rough idle.

I sent mine off to www.cruzinperformance.com and they cleaned and calibrated them for about $15 each with new seals. They always give you the "before" and "after" numbers. He has done about 5 or 6 sets for me over the past few years and always does a great job.

You could do a lot better than Fram filters IMNSHO. http://www.knizefamily.net/minimopar/oi ... rence.html

Correctly sized tires (205/75/15) were a help for mine.

I am not familiar with the 99 valve covers, but I ended up using a valve cover gasket and a dusting of Hylomar (my favorite flange dressing) to get mine to seal correctly. A PITA to do as it is a poor design right from the factory.. Correct torque on the valve cover bolts is a plus also. The rear ones are awkward to get to. I have to retorque all of them on a regualr basis, but I am not sure if using a LockTite product on them is a good idea or not, so I have not.

Does anyone here have a dyno sheet for a stock 4.0L engine? It might be interesing to look at.

Did you buy the the full metal oil pan gasket from the dealer? Worth every nickel. I used a bit of Hylomar to get it used to being on there. I also "spoke shaved" the sharp edges off the block where the rear main oil seal goes in so that it did not "snag" going in. Could it be leaking from the valve cover?

I would first do a compression test properly (warmed up engine, wide open throttle, fully charged battery) to see what is happening in there right now. Then I would do the squirt of oil in there and repeat the test to see if that changes anything. You may need to follow it up with a leak down test to see just where the compression is leaking out from.

Have you seen this little chart for NGKs? http://www.spark-plugs.co.uk/pages/tech ... l_code.htm

I get my injectors serviced here with really good service. He has done about 6 sets for me know. http://www.cruzinperformance.com/

Been here? http://www.lunghd.com/Tech_Articles/Eng ... Stator.htm

Sorry I am afraid my terminology is dated. :oops:

Have you tested the Hall Effect Sensor?

I will defer to others (as I am more used to other FI systems) but wouldn't that vacuum loss pose a problem for the fuel pressure regualtor and make it run rich?

I went back to stock tires (205/75/15) as the ones on there before (235/75/15) geared me up too much with my 3.07 axles. I just ran out of torque too often. If you go here http://www.1010tires.com/TireSizeCalculator.asp you can compare various sizes at the same time.

There have to be lots of folks out there with a wide band that you can use. Mine is loaned out right now. :driving:

Why are you removing them? If it is to replace them with fresh hoses that is OK to do.

My 1990 MJ stock 4.0 5 speed 3.07 axles Michelin M/S 205/75/15s gets 22-23 mpg Runs 2250 RPMs at 70 mph 33 x 10.5 x 15s are 18.08% taller than stock and will throw off the odometer unless you have corrected for it.

Been here? http://www.ratwell.com/mirror/interro/techgas.html A little tuning time with an LM-1 is worth it.

Ever tried these BT 703 battery cable clamps? http://www.tsunamionline.com/product.php?id=37

I have a set of Thule 421s on my longbed. They work really well. http://www.amazon.com/exec/obidos/ASIN/ ... ch66347-20