draye

Checked as you said, black to white.
Closed throttle: 760 Ohms
Open throttle: 4390 Ohms

mrholmquist

how about white to red

draye

Checked white to red
Closed throttle: 4650 Ohms
WOT: 1000 Ohms

This engine started a couple of days ago after several attempts and ran for 7-10 minutes. Ran it at 2500-4000 (just below clutch engagement) revved it a few times to make sure clutch engaged and track turned and brakes worked. Shut it off. Since then it hasn't re-started!

Checked the following items:

Stator is tight and static timing is where it belongs.
Fuel pump cycles as it should, output is 40 PSI
Have good spark at normal closed throttle and WOT.
Compression is #1: 125+, #2: 110+, #3: 125+.
Fresh premium fuel, new fuel filter.
Exhaust is unrestricted.
Fully charged dry cell type race battery, tests at 12.8 volts
Two new sets of NGK plugs BR9ES and BR9EIX gapped at .028"
Crankshaft checked and is 'in phase'. Firing 1-3-2 every 120 degrees.
ECU flashes code when one injector is disconnected.
Checked wire between CDI and ECU and it has continuity.
All grounds cleaned and checked.
All injectors show close to proper resistance (2.6/2.7/2.8 ohms)
(they won't spray with fuel rail fuel, but they will with fuel pump running)
ECU is flashing "11", after I did injector test. It didn't before.
Engine will not fire with fuel poured into spark plug holes.
Engine will not fire on starting fluid.
TPS checked, it seems to be malfunctioning when i do voltage test.

mrholmquist

hmmm.....sensor seems to be ok when tested with ohmmeter. 5.0v supply from ecm on red seems ok. signal voltage on white is too high causing code. Possible cause is bad ground on blk. Better check that one . The ground is supplied by the ECU at terminal # 5 but the wire has a splice in it because this wire also grounds the air temp sensor.

Disconnect ECU , the TPS and the Air temp sensor. Using your ohmmeter make sure the path is good between the TPS harness black wire and ECU terminal #5. Then verify the wire also makes good contact with the black wire that goes to the temp sensor. wiggle the harness while testing in case the connection is loose. Also check that temp sensor is not shorted using your ohmmeter. You should get about 2.5 k across the sensor at room temperature


Also thinking .....check that white and red wires are not shorted together when the sensors and the ECU are disconnected. If there was a short between these wires it would explain the readings you are getting. Pay close attention to the connectors if the wires were pulled out of place they could be touching inside the connector.

draye

Ok, here’s the results of my recent tests
Checked resistance of ATS air temp sensor: 3760 ohms

Unplugged connector at TPS, checked resistance between black and white wire:
Closed throttle: 790 ohms
Open throttle: 4360 ohms

Unplugged EFI connector
Checked continuity from TPS connector to EFI plug
Red wire at TPS connector to pin 17: good
White wire at TPS connector to pin 11: good
Black wire at TPS connector to pin 5: good

Plugged TPS connector together
Checked TPS resistance pin 5 (black wire) to pin 11 (white wire) at disconnected EFI plug: open, no reading

Checked TPS resistance pin 5 (black wire) to pin 17 (red wire) at disconnected EFI plug: open, no reading

Disconnected Air Temp Sensor

Checked TPS resistance pin 5 (black wire) to pin 11 (white wire) at disconnected EFI plug: open, no reading

Checked TPS resistance pin 5 (black wire) to pin 17 (red wire) at disconnected EFI plug: open, no reading

I don’t get it! I should have same resistance values checking white to black wires, whether I check them at EFI plug with TPS plugged in or check at the sensor with the sensor unplugged from the harness. Checking at EFI plug with TPS plugged in is the same as using an extension wire.

mrholmquist

you are 100 percent correct if the sensor checks out and the harness checks out then you absolutely have to get the same readings at the ecu connector. You are missing something somewhere , there is a logical explanation . Check it again......

Make sure the terminals are not spread open at the connector . Sometimes they get damaged (bent open)
if you are not careful when testing them.

if this happens there will be no terminal grip and no connection, this will cause this kind of problem and those kind of readings

draye

When rechecking the TPS (connector unplugged) clipping alligator clips to the prongs. Testing is hit and miss, need to wiggle/reclip/fiddle around to get a reading! Suspecting the connector is bad. Am going to wire in (3) individual plugs and see what happens.

draye

Update:

Disconnected wire from CDI to EFI

Repaired TPS connector (faulty connection at connector plug)
I wired each lead with it’s own separate plug.
Resistance (black to white wire) is:
810 Ohms at closed throttle.
4460 ohms at WOT.

Poured fuel into cylinders thru spark plug holes
After 4-5 pulls, engine fired and ran for 10-15 seconds

Reconnected CDI wire to EFI

Poured fuel into cylinders thru spark plug holes
After 4-5 pulls, engine fired and ran for 5-10 seconds

Hooked fuel pump directly to battery, so it would run continuously.
Poured fuel into cylinders thru spark plug holes
After 4-5 pulls, engine fired and ran for 5-10 seconds

Seems as though injectors are not firing (spraying).
The last time I checked them manually they would only spray with fuel pump running, by manually grounding each injector.

Seems now the engine is starting but only running till fuel added to cylinders is burned up. Seems there is no fuel being injected into the motor.

draye

i forgot to mention, after i repaired the TPS connection the previous "11" fault code is gone.
no other fault codes

draye

UPDATE:

Hooked up VOM on CDI output wire (to ECU) set to 20V scale, pulled 3 times, VOM read 4.8v/4.7v/4.85v
Hooked wire back up to ECU

Pulled rope once, fuel pump cycled.
Pulled rope second time, STARTED AND RAN !!!!

Took it off the stand, drove it for 2 - 2 1/2 miles, several laps around the house and a couple of laps around the field/pond.
Lower half of air box off, but air temp sensor plugged in

Drove it back into the shop, turned it off

Now it won't restart! It fires but won't start.

Fuel pump is cycling on every pull.

draye

UPDATE:

Walked back out to the shop this evening, pulled rope, started first pull.

Didn't dare let it go to 'idle', kept a couple of flat washers between throttle and housing to keep RPM up around 2000+ RPM when I went in the house to get gloves and mask.

Drug it out of the shop, while running, put 10 miles on it. It seemed to run good on the trails!

Pulled into shop, let it go to 'idle' dropped below 1000 RPM and died.

Tried restarting after it 'died', no start. I will try again in morning.

How do i adjust idle RPM and what should it be? I seem to remember this idled at around 1500+, but that's kind of a guess.

Is there anything I need to adjust with regard to TPS housing (I noticed it is slotted).

joshkidner

dont know alot about efi, but i believe a good idle is between 1800-2000 depending on your sled. I go by sound of ear. I can hear the sweet music of a good idle.

__________________
1987 chasis with 1985 597cc under the hood. Xtra-10, fox shocks, and a whole lotta speed!

RJ Gleason

You may have the throttle cable too tight and that makes the lever hit the TSS pin switch.
There are two things to try here.
1. use the throttle stop adjuster screw to increase the idle.
2. relieve some of the tension on the cable so that you have 30 thousands clearance between the throttle lever and the throttle block.

__________________
Old Cat Rider
'93 Wildcat 700EFI
w/ Comet 108 Pro-4 clutch & 01 ZR skid

'90 Wildcat Project in progress.

Vintage (sorta)
1980 Indy Trail 440 (for sale)
1980 AC Pantera (donor engine to the 90 wildcat)


http://www.dcdrifters.net/


Senior Warden; F&AM Dryden Lodge# 472
http://www.masonicdryden472.org/

Rules of this forum are strictly enforced!

draye

Update:

Engine has been starting fairly reliably lately, have put maybe 20-30 miles on it,
However, idle seems erratic.

Sometimes it will run at 3500-4000 on initial start up and come down to 1800-2000 after a few minutes. Other times it will stay at high idle and sometimes normal idle.

Sometimes even after extended run time (a few miles on trail), it will still idle high, sometimes it will idle normally.