injectors not spraying

[tony070804]

fuel to rail, rail has bout 40lbs of pressure, good spark to all four plugs, injectors not spraying at all. each have bout 2.3 ohms and lil over 12v to the injector plug. The car did sit for over a year so im thinking they may be gummed up, is it possible for them to get completely gummed? if so is there a way to clean them without the car running?


on a different note can you run a 550cc injector with a stock turbo and motor? only reason for asking is I found a really good deal on a set, and these turn out to be bad I can get the 550's cheaper than the 450's

 

[pos4g63]

It will run but not very good and probably be super rich.

 

[delta448]

fuel to rail, rail has bout 40lbs of pressure, good spark to all four plugs, injectors not spraying at all. each have bout 2.3 ohms and lil over 12v to the injector plug.

What Cam Angle Sensor is on this car, and is it known to be good?

The car did sit for over a year so im thinking they may be gummed up, is it possible for them to get completely gummed?

It's possible they are gummed up, but not really likely that all of them would be completely inoperable.

if so is there a way to clean them without the car running?

Yes, but you're not going to want to do it. You will be more inclined to just uninstall them and send them to someplace like FIC to have them cleaned and flow-tested.

on a different note can you run a 550cc injector with a stock turbo and motor? only reason for asking is I found a really good deal on a set, and these turn out to be bad I can get the 550's cheaper than the 450's

You can run any size injector you want as long as the ECU is programmed/tuned for them.

If you just swap out injectors the ECU doesn't automagically go "oh wow, those look like some sweet RC550's, so I'm going to use X deadtime and Y pulsewidth for this". -If you just swap in bigger injectors without tuning you'll be running very rich, losing a lot of power, getting absolutely horrid gas mileage, destroying your piston rings and ruining your engine oil.

 

[tony070804]

Nothing is known about the cam sensor. Would that keep the injectors from spraying at all though? They are getting power.

 

[clipto]

Some injecters have a pop off pressure which means that you fuelpump has to give it a certain amount of pressure before they will spray. If that helps with anything.

 

[tony070804]

Well its getting 40lbs of pressure to the rail. Is that enough?

 

[dmaffo]

What Cam Angle Sensor is on this car, and is it known to be good?

It's possible they are gummed up, but not really likely that all of them would be completely inoperable.

Yes, but you're not going to want to do it. You will be more inclined to just uninstall them and send them to someplace like FIC to have them cleaned and flow-tested.

You can run any size injector you want as long as the ECU is programmed/tuned for them.

If you just swap out injectors the ECU doesn't automagically go "oh wow, those look like some sweet RC550's, so I'm going to use X deadtime and Y pulsewidth for this". -If you just swap in bigger injectors without tuning you'll be running very rich, losing a lot of power, getting absolutely horrid gas mileage, destroying your piston rings and ruining your engine oil.

Totally true, you have get a chip made (cheap) or ecm link (bit more $ but in long run worth it) or some way of telling ecu what you have done.

 

[Spyderman7]

Have you put a noid light to any injector plugs and watch them pulse? If they are pulsing and there is no fuel on the spark plugs or doesn't smell like fuel then the injectors are frozen or something.

 

[delta448]

The 2G ECU has to have a correctly aligned signal from the CAS and the Crank Position Sensor in order to fire the injectors in proper sequence. That's why people have to swap injector harnesses around (or ECU pins) along with the plug wires when they use a 1G CAS (or 2Gb CAS) on a 95-96. The 95-96 CAS is located on the opposite side of the cylinder head and produces an inverse of the signal produced by all other year sensors.

If your intake cam timing mark is not misaligned to the crankshaft timing mark, make sure that whatever CAS sensor you're using is good, and if it's not the stock one on the intake cam sprocket, then makes sure everything I mentioned above is wired correctly for the swapped sensor.

 

[tony070804]

Car is completely stock. Is there a way to test the cas sensor without the car running? Whatelse could it be?

 

[2slow4now]

I had a bad 1g cas sensor and I had a similar issue. You can take those off the head and turn the key to "on" and just spin the sensor shaft to hear the injectors function. I couldn't figure out why mine was doing it because it came off a running car. I unhooked it and hooked up my old crank sensor, turned the key to "on" and passed the trigger plate through it and click click the injectors functioned. I bought a new cas and it worked right away.

You have a 95 so the cam and crank pos are on the pulley side of the engine or did someone put one on the intake cam like Delta448 said?

 

[delta448]

It could be bad/broken wiring or possibly blown ECU drivers I suppose... but really, I'm pretty sure the CAS is your problem.

The only ways I know to test it is to use an oscilloscope to view the output waveforms, or swap it with one that works fine on another 2Ga.

Can't spin the 2Ga sensor to check, since it uses a trigger plate on the cam sprocket and the sensor part is really just a pickup like on the crank sensor.

 

[BurrowZ]

If it sat for a while, sometimes critters like to gnaw on stuff on the firewall and take off some of the material to build a little nest in the car. So, check your injector resistor pack as well.

It's a long shot but could work. There is a thread on how to test them somewhere, and also check the wiring to it.

 

[delta448]

^I hadn't thought of that, -good suggestion!

 

[2slow4now]

It could be bad/broken wiring or possibly blown ECU drivers I suppose... but really, I'm pretty sure the CAS is your problem.

The only ways I know to test it is to use an oscilloscope to view the output waveforms, or swap it with one that works fine on another 2Ga.

Can't spin the 2Ga sensor to check, since it uses a trigger plate on the cam sprocket and the sensor part is really just a pickup like on the crank sensor.

Thats what I used to see my 1g cas was bad. A stock 2ga crank sensor and a spare trigger plate that I just passed through the sensor to simulate the crank turning the plate.

 

[tony070804]

So is there any way to test the cam sensor? The car will turn over all day long, fuel is getting to the fuels rail, spark is good on all 4 cylinders, but injectors will not spray. Resistance is good on injectors, and 12v on the injector plugs. With that said the only thing I can think of would be a bad cam sensor so is there a way to test it?

 

[delta448]

2G Turbo ECU Pinouts

RRE Instructions

Verify continuity to the ECU on the wiring harness, if the wiring is good, find somebody to swap sensors with you or get a new one, unless you can gain access to an oscilloscope. You might get really lucky and be able to get a parts store to rent out a nice DVOM with a small screen signal analyzer.

 

[Mr Peepers]

Just a shot in the dark, but if the injectors are "frozen," try starting the car with 0 fuel pressure in the rail and the fuel pump wires unplugged. The fuel pressure can make them harder to open if they are already being stubborn and this helps to "wake them up." This has worked on a couple of e85 cars that sat for a while and seems much more common in them. Check with a noid light first to make sure they are getting a signal though.

 

[tony070804]

Oh man I honestly can't believe that worked! I've never heard of that! Well she's alive again, thanks for everyones help! Especially Mr peepers!

 

[delta448]

Wow. I'm impressed Matt, rep inbound.