24x issue

[97firehawk]

So my cousin did a 24x swap on his 96 impala and so he sent the computer to get a base tune at the speed shop before he took it in to have them tune it .
The car would crank ans pop but finally start but it didn't really want to idle.

He got the car to the tuner and he said that he couldn't read the cam sensor and so he tried another and still the same , so my cousin took it home to sort it out 4 different cam sensors later still have the same issue , he made sure that the little cam nub was the proper length and it was there's no interference with the sensor either he has power to the sensor but the computer isn't reading the signal.

What could it be something that is not right in the tune or maybe a bad computer? He's out of idea's and i don't have anything either.

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[Ryan Stout]

Make sure the injector firing order is correct. On HPTUNERS it'll read 1001 0110, that needs changed. Not sure what to, but I can look. Also make sure they deleted one of the knock sensors, LS came with 2 of em. When I bought my 24x, they changed the coil firing order in the harness so I didn't have to change it, but make sure it's correct also.

[Ryan Stout]

What timing set is he running?

[Ryan Stout]

Another thing, take a meter to it and make sure it's getting 5v to the sensor. If not, there's plenty more 5v sources from the pcm. May try another one.


Sorry for blowing your thread up. I fought my 24x for a while....kinda wish I would've gone megasquirt by now.

[97firehawk]

He does have 5 volts .

He has a single row lt4 HD timing chain .

Bp automotive did his harness and i believe he did the injector swap for him .

The tuner wasn't very helpful and didn't seem to want to give him any information about the tune so we don't have a clue what his tune looks like


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[harner]

Cam sensor or crank sensor? The crank sensor will need to be relearned. My base tune from BP Automotive was decent for my setup.

I agree about the fuel injectors - The BP harness is awesome but he doesn't label which cylinder the connector belongs, so the passenger side connectors were backward. Didn't take long to figure out the issue and it was an easy fix, but something to check.

Good luck

[97firehawk]

Cam sensor. The crank relearn was done .

I will have him double check the injectors.

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[Rhett954]

I fought my wiring harness and ended up getting a new harness thru BP automotive. I also ended up having to buy a 2nd cam and crank sensor to get it running on top of the ones that came with the 24x kit.

My experience and research is that the car will start with a bad camshaft sensor, but it will have a long crank time.

I also went thru 2 different pcms and am on my 3rd one before I got it all working (wiring issues).

there are ways to check the output of the sensors by disconnecting the blue connector at pcm and using a meter on the correct wires. My notes are out in the garage though.

[shownomercy]

Cam sensor is not needed to run, it will start..albeit shitty cause the PCM guesses which bank is where.

I would look into verifying correct coil is at correct cylinder.

Does it have nasty backfires?

[97firehawk]

It has a decent pop on the first few cranks , then it fires up . On the first base tune it would rev up half as decent for a little while, them it would get up to temp and stop wanting to rev up .

The second tune it doesn't want to rev at all .

Let me see if i can get him to join the forum finally so maybe he can give some better information so that you guy's can maybe get a better idea. I really appreciate the information from all of you.

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[97firehawk]

He said he did double check the the injectors and coils .

He said the cam sensor is reading and sending signal to the computer but the computer isn't reading it .

So he's going to try another computer . Does anyone have any recamended tuners for a quality base tune he wants to try someone else



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[Rhett954]

You guys could bring the pcm over and try it in my car this weekend if you want.

I was real happy dealing withTj at Baker Engineering.

Look on www.car-part.com for another pcm, I got 2 out of a junkyard in Lansing for $60.

[97firehawk]

TJ is who was doing the first base tune and who was suppose to finish the over all tuning but he keeps putting it on the,back burner and he hasn't really seemed very interested in helping figure out the issue . I know he's a great tunner. He said maybe this winter but my cousin wants to drive it at woodward bad .


Hell i did realize that you were in Jackson hahaha cool .

im not sure what he wants to do let me ask him

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[97firehawk]

He said if you are ok with it he like to give it a try

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[Rhett954]

Let's shoot for Sunday, I am going to Milan tomorrow night for heads up and Saturday I will be finishing up the ctsv brake conversion on my car.

My tune is olsd with no 02, 42# injectors.

I will pm you my phone#

[97firehawk]

Hmm , not sure if you want to put his in his is with O2s and i believe 65 pound injectors . I don't want to hurt your engine . It might be ok at idle for a short time . The thing we are looking for is an automatic ses light for cam sensor and a somewhat decent idle .

But Sunday is fine . I just don't want to hurt your engine .

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[shownomercy]

If cam has power and signal is getting to PCM, I would see if you can read the output waveform on a maximus/tech2 etc. At that point, you prob need a PCM, but I would be worried what caused it to die.

[Rhett954]

This is some help I got from Mike Noonan at EFI connections when I had trouble with my crank sensor not working. You should also be able to check the output of CMP sensor at blue 73 following the same troubleshooting idea. The pcm supplies its own power and ground to each sensor from the red pcm connector and the signal from the sensor is in the blue connector.



Test the function of the PCM/harness at the crank sensor:
· Disconnect the crank sensor connector.
· Turn the ignition key to ON.
· With a multimeter, test for 12V on connector cavity A
· With a multimeter, test for ground on connector cavity B

If this does not check out okay, you have a problem related to your wire harness or PCM.

If this does check out okay, test the crank signal.
· Turn off ignition.
· Disconnect battery.
· Connect crank sensor connector.
· Remove PCM connector (just the connector with blue retainers)
· Connect battery.
· Turn ignition on.
· With a multimeter, test for voltage at PCM BLUE connector PIN 12. This is the crank signal circuit. Rotate the engine BY HAND. As you rotate the engine, the voltage will go high when a tooth passes the sensor and voltage will go low when a reluctor gap passes the sensor.

[97firehawk]

Rhett954 , thanks alot for letting us swing out a try his computer and for taking us for a ride in that Awsome car of yours. Also for coming out and trying to get his car figured out .

Small update he found out he only had 18 pounds of fuel pressure and found out his line wasn't hooked up all the way so now the car runs great and idles and lays rubber better than before . Just a mail order tune hahaha.



But his cam sensor is still an issue . And he is going to try a few things today to see if he can get it working
.

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[97firehawk]

http://images.tapatalk-cdn.com/15/08/14/3b525ec1be3ddbbf33f6356a8970d90e.jpghttp://images.tapatalk-cdn.com/15/08/14/b2d1396f7ecf2f497b910ca99630afab.jpg

He said he was rolling and when he rolled into the throttle it just smoked them mickeys off , he had to let out of it with plenty of power to spare . And still need to figure out the cam sensor .

Im surprised that he is getting into it until it's figured out.

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[shownomercy]

Again, cam sensor doesn't affect running AFAIK, call and confirm with Mike at EFIconnection.

[97firehawk]

It's running well but it cranks forever before it starts . We know it will run without it but it's still an issue trying to figure it out. he has talked with mike at EFI connections, he's trying everything he has said. He's having a guy we know locally that is good with electrical automotive stuff take a look at it to see if he can figure out what the issue is .

It's just strange that the scan tool will count the cam signal but the computer doesn't recognize it .

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[gmpowered]

It's running well but it cranks forever before it starts . We know it will run without it but it's still an issue trying to figure it out. he has talked with mike at EFI connections, he's trying everything he has said. He's having a guy we know locally that is good with electrical automotive stuff take a look at it to see if he can figure out what the issue is .

It's just strange that the scan tool will count the cam signal but the computer doesn't recognize it .

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What pcm are you using? Does the tach work? The cam sensor drives the tachometer. No tach no signal. If the tach works the pcm is reading it.

How do you know the pcm is not reading it?

It will run without it, hard starts is a typical symptom.
If you are using a tech2 do a case learn, it could fix it. It syncs or orientates the crank and cam. Hptuners does it also.

[97firehawk]

The tuner said it wasn't working plus it kept throwing a engine light for it .
Also the tuner could not get hp tuners to do a relearn , we had to get the tech2 to get it to work.

The engine light is off now and the tach is working now and he has the 12200411 computer

So maybe it just needs a better tune at this point

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[97firehawk]

I just talked to him and he had a guy we know take a look at it and he said that he thinks its the computer because there several sensors not reading corectly, the temp sensor was showing -40 at full running temperature hahaha so

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[gmpowered]

The tuner said it wasn't working plus it kept throwing a engine light for it .
Also the tuner could not get hp tuners to do a relearn , we had to get the tech2 to get it to work.

The engine light is off now and the tach is working now and he has the 12200411 computer

So maybe it just needs a better tune at this point

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In all honesty if your tuner doesn't know how to case learn a car RUN.

What OS are you running on the pcm?

I highly doubt the pcm is the culprit but i wouldn't rule it out. To me someone who cant do a case learn probably has larger issues with the tune.

The pcm reading -40 shows there is either 0 or 5v. I belive it would be no voltage at -40. The sensor could be bad or there is a bad connection. You can put 5v to the water pump plug and see what the scanner reads. You could also run 5v to the pcm to see if it changes. That would rule out the pcm.

[superspirit]

If the temp sensor is telling the computer that it's below operating temp. then it will not run and complete the CASE learn.

[gmpowered]

If the temp sensor is telling the computer that it's below operating temp. then it will not run and complete the CASE learn.
Why would it work with a tech 2? They require 150* IIRC to run it. HPT is higher, maybe a low temp thermo was the cause. Or a bad connection.

[97firehawk]

I've read that sometimes hp tuners has trouble doing a relearn and that people have had to use a tech 2 , i am not sure why .

The tuner is very well known for his work but im not sure what all he was having an issue with because he's not a very talkitive, i wasn't there when he picked the car up . My cousin going to try another computer in hopes that it helps .

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[Rhett954]

I did finally measure my crank sensor when the ignition is on and I am getting 000 ohms to ground. On this impala we were getting 80-85 ohms. Added a second ground wire from the block to frame and then measured 70-75 ohms - this was from the ground wire at the sensor to the grounds on the head.

I am pretty sure it is the pcm after seeing that.

[97firehawk]

New computer didn't seem to help, so he started to triple check the grounds and found that his battery ground wasn't up to par so he fixed that and that did the trick . He has a battery relocation to the trunk .

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[Ryan Stout]

I hate stuff like that. Glad you found it!

[97firehawk]

One other issue that we found is that the cam sensor wasn't close enough to the reluctor .

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