Need help trouble shooting

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LisaMartinez
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Need help trouble shooting

Postby LisaMartinez » Fri Feb 14, 2020 4:46 am

First 1990 Chevy Beretta GT 2nd owner with only 109 original miles . Ran great for a few months. Then
Ran out of gas taking daughter to school, pulled it home got gas in it and it hasnt' started since.
Read codes with paperclip but I think it was a 21 or 23 the throttle position sensor replace that then code went away then replaced fuel pump. I have good spark on all 3 coils ???



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heavywoody
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Re: Need help trouble shooting

Postby heavywoody » Fri Feb 14, 2020 10:34 am

Did you change the fuel filter? If you ran it out of gas, then the sediment at bottom of the tank could have been sucked up by the pump and thrown into the filter, clogging it and preventing fuel from being delivered.


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95 Z26 Turbo 3400 5spd - R&D Project
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ifixalot
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Re: Need help trouble shooting

Postby ifixalot » Fri Feb 14, 2020 12:03 pm

I have changed fuel tanks and pumps on most all of my cars. I have never encountered sediment in the bottom of any fuel tank.
In addition, there is a sock on the end of the pump that filters the fuel before it enters the pump. I doubt the fuel filter is plugged up.
Perhaps they just put a couple gallons in the tank and it's not enough for the pump to suck up.
I'd put at least 4 gallons in the tank. I'd turn the ignition switch on for a few seconds and then off several times to let the pump prime the system.
Then try and start it.



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woody90gtz
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Re: Need help trouble shooting

Postby woody90gtz » Fri Feb 14, 2020 2:38 pm

Did it definitely run out of gas? The gauges aren't always trustworthy. Could be a bad connection at the fuel pump and sending unit.

I've actually run mine out of gas before with a gauge on 1/2. Thought I had a dead fuel pump. Haha


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Rettax3
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Re: Need help trouble shooting

Postby Rettax3 » Fri Feb 14, 2020 8:25 pm

woody90gtz wrote:Did it definitely run out of gas? The gauges aren't always trustworthy. Could be a bad connection at the fuel pump and sending unit. I've actually run mine out of gas before with a gauge on 1/2. Thought I had a dead fuel pump. Haha

My 'old' '95 Z-26 had a similar issue when I got it -I had initially sold it to my niece after getting it running, and warned her that 1/4 meant fumes -she still ran it dry enough times to kill the pump. :roll:

I would advise getting to an auto-parts store and using their loan-a-tool fuel pressure gauge, or just buying your own. The test port is under the intake manifold, accessible from the side on your 3.1, normally protected with an aluminum cap. You should have roughly 35-40 psi with key on, engine off, and you should be able to hear the pump running for a few seconds. I would also suggest checking the fuel-pump fuse, to make sure the old pump didn't blow that when it went out. Your car also uses a large relay, mounted on a bracket behind the engine on the firewall with three others, and those can go dead after this many years, especially if it received a heavy load which could be caused by an overloading pump... Try switching the relays around to test them -the fuel pump relay will have an orange, a red, and a grey wire, I think it has green too but don't recall the fourth color for sure off the top of my head...

Ifixalot is right about priming that pump by turning the ignition on and off several times (or bumping the starter), but if you do it too quickly, the computer won't run the pump to 'prime' each time.

A common problem when replacing pumps is not getting the connections right, or leaving the hoses loose. I've also noted a sad trend to delete the 'pulsator' (the little oval housing mounted to the top of the pump's outlet pipe), and this is a terrible idea, no matter WHAT the new pump manufacturer says...

If your car has the digital dash gauges, you will have an extra black ground-wire too (four wires total), which can be confusing.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

LisaMartinez
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Re: Need help trouble shooting

Postby LisaMartinez » Sun Feb 16, 2020 5:18 pm

Already replaced fuel pump.Just pulled off fuel injectors cleaned them tested them all put them back in. just replace the crankshaft position sensor,spark plugs and wires I'm getting spark on all three coil. The two second fuel relays there when you turn the key.???? And I am one of them determined bitches that get stuff DONE. I do not finish a project without completing it . But I've never been stuck on something like this please read next post



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Postby LisaMartinez » Sun Feb 16, 2020 5:28 pm

How can a retailer tell or show you how to test there own product and you test it everything tested good and they still tell you that the product is defective, because I just ran and ignition control module test and I'm getting power (12 volt ) my ground and signal and they say it's Defective, also did a resistance test setting multimeter to ohms on the coil side not the connector ,to crank shaft position sensor and getting 600ons????



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Rettax3
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Re: Need help trouble shooting

Postby Rettax3 » Mon Feb 17, 2020 2:31 am

1. Did you verify actual fuel pressure, at the rail with a gauge on the test port yet?
2. You said you have spark, did you put a spark-tester on each plug and look for positive indication while cranking?
3. If the suspect 'retailer' performed a module test on your ICM (Ignition Control Module) and they said it is defective but you doubt that, then ask them to show you a 'pass' test on one of their brand new modules to prove the test equipment, but if you don't believe the module could be faulty, why did you bring it in for testing in the first place?

The ignition systems in these cars are nearly fault-proof, basically they work right or don't work at all. Intermittent failure is the only other option on this, so if you are watching for spark with an inline tester and the coils are producing spark while cranking, then the engine should either start running or the problem ISN'T in the ignition system. You have definitely done a lot of work here, and started by doing the hard jobs first, at least it should be easy to fix the issue now once you can find it. If everything else tests good and by all accounts the engine SHOULD BE RUNNING, then look at the catalytic converter. Simple test is to REMOVE the oxygen sensor (don't just unplug it, it must be taken out completely) and try starting the car again. If the cat is plugged, exhaust cannot get out of the engine, and it won't run, removing the O2 sensor gives it a place to go. Typically, you would at least get a cough and a chug out of it though... Last real possibility is a dead ECM, or computer. Rare, but it happens, and will happen more often as these cars age. Good luck, keep us posted.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

LisaMartinez
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Re: Need help trouble shooting

Postby LisaMartinez » Mon Feb 17, 2020 1:06 pm

heavywoody wrote:Did you change the fuel filter? If you ran it out of gas, then the sediment at bottom of the tank could have been sucked up by the pump and thrown into the filter, clogging it and preventing fuel from being delivered.

Yes and disconnected fuel pump after filter and ren fuel pump and everything is clean



LisaMartinez
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Re: Need help trouble shooting

Postby LisaMartinez » Mon Feb 17, 2020 1:17 pm

not that I'm ignoring you have six kids and only look at my phone when I have time but very eager to get this car running we have no vehicle at the moment. What controls my gas from getting to the engine?



LisaMartinez
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Re: Need help trouble shooting

Postby LisaMartinez » Mon Feb 17, 2020 1:37 pm

What makes me believe it's not that is because when I had the injectors Off cleaning them borrowed noisy lights to see if I was getting any kind of injector pulse . had one injector and noid light in, out of the six on injector rail. And I had T-Pined one of the four wires that are on the connector that goes to injector rail, got too cold went in, the next morning came out forgot the t-pined was in . Started testing something else was moving the wires the T-Pain touched the motor and it started working, noid light came on my injector spit out fuel and that's the only way I can get my Fuel to come out????? That's why I had asked what controls my gas from getting to the engine seems like something is not letting the gasket to my engine but I know it's that power and it's working because my GM has a fuel test wire right in the front firewall the driver side if I were to take that wire and put a fuse on it and attach it to my power on battery my fuel pump will stay running. I have one more question can I try starting my car while doing that?????



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heavywoody
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Re: Need help trouble shooting

Postby heavywoody » Wed Feb 19, 2020 3:37 pm

Have you checked the resistance (ohm'ed out) the injectors with a meter?


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95 Z26 Turbo 3400 5spd - R&D Project
Beretta Preservation Society - Director of Acquisitions
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Rettax3
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Re: Need help trouble shooting

Postby Rettax3 » Wed Feb 19, 2020 5:03 pm

It is a little difficult to read your posts, I think your phone is auto-correcting some of your words into things that don't make sense... Technology, wonderful thing. :pardon:

Your fuel pump is energized by either the Normally Open side of the fuel pump relay that I mentioned (orange wire, this gets power from the fuel pump fuse) or the Normally Closed side of the relay (red wire, this gets power from the computer for a few seconds during 'prime' mode, or from the test-lead near the fire-wall if you hook power into it). This power goes out from the relay (grey wire, some cars used tan instead) to the pump and powers it. Also supplying power to the pump on that grey (or tan) wire is the oil-pressure sensor on the front of the engine -basically if there is enough oil pressure, it will activate the pump that way.

If you run a power wire to the red test-lead connector, the pump will run continuously, whether the engine is running or not (not a good idea, old or cheap injectors can leak a little, and you could end up hydraulic-locking the engine or even starting an engine-fire) and if the power isn't shut off or disconnected, it could run until the new pump is fried or your battery is dead. Check the fuse and the relay, that is probably where your problem is, and if it was the fuse, make sure you find out what blew it -probably the old pump, but maybe not.

If you are looking at the other side of the fuel system, the injectors, they are powered through their fuse as soon as the key is turned on. This fuse is inside the box in the dash, you have to open the driver-side door to get to it. The computer grounds the injectors out in micro-second pulses. Running a fuel injector continuously for even a second or two risks overheating its' coil and burning it out. You have three fuel injectors on each circuit, and two circuits (pink and pink/black wires carry power from the fuse box, blue and green wires go to the computer under the passenger-side dashboard where they can be grounded inside the computer). The computer controls the pulses' frequency, based on RPM from the ignition Control Module and Crankshaft Position Sensor (make sure the yellow and purple twisted wire from that sensor is in good shape or the engine will not run). It runs the pulses longer or shorter times (still fraction of a second) based on engine load, as it calculates throttle position sensor, RPM, and intake air pressure (vacuum, read by the MAP or Manifold Absolute Pressure Sensor) and also very importantly engine coolant temperature*. The oxygen sensor helps the computer adjust and fine-tune the fuel pulses once it gets hot enough to work.

*As a note for you, if this coolant temperature sensor (two wires, one is black and one is yellow -unless you have the digital dash gauges, you also have a one-wire (green) sensor that controls the temperature gauge in the car, so even if that reads right it doesn't mean your computer is getting the right temperature reading) goes bad or gets disconnected, the computer can get so confused that the engine will get too little or too much fuel, and likely won't run, or almost certainly won't run well enough to drive. If you know you are getting fuel pressure, noid-lights confirm you are getting pulses to the injectors, and an inline spark-tester proves you have spark but the engine still won't run, the coolant temperature sensor would be the next place to look. Good luck.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

LisaMartinez
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Re: Need help trouble shooting

Postby LisaMartinez » Thu Feb 27, 2020 3:10 am

20200221_180601.jpg
Relay under steering



LisaMartinez
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Re: Need help trouble shooting

Postby LisaMartinez » Thu Feb 27, 2020 3:11 am

20200221_180620.jpg
I think was main relay
20200221_180620.jpg
I think was main relay




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