Check engine light on, code b2600

You have half of the process. You ground the green wire then you need an LED test light connected between pins one and two Then count the flashes on the LED. If it's an engine code it should be in the attached chart. Pull the code(s) and post them and we can see what the issue is.

thank you very much.

You are welcome. Did find any codes or just not have much time to mess with it yet?

I am confused about one thing. I am using a test light between terminals one and two, not an LED test light. Is there a difference? When I look up LED test light it looks like a regular test light.The test light did not flash, the check engine light on the dash did not flash.

Needs to be an LED light and attached so the ground is on pin 1 and the tip is on pin 2. Then the LED will flash the codes. The LED blocks current in one direction and that tells the ECU to go into diagnostic mode.

thank you. I will pick one up and try it. I was just using a continuity test light, no doubt that was my problem. I will post back.

Hi,

I noticed we haven't heard from you for a couple of days. Has any progress been made? We're interested in knowing.

Take care,

Joe

got the LED light and it flashes, trying to read the flashes.

The easiest way to do that is to set it up and just start counting the flashes, write them down and then stop when you see them start to repeat again. So say it flashes 1-4, then 0-3 then 1-5 then you see 1-4 again, Stop and the codes are the 2 digit numbers you find. If you really have a problem see if you can record them in a video and post that on here and we can try reading them.

Negative battery cable clamp was kind of dissolved, wouldn't stay tight. thank you for your help.

Loss of ground would cause a few issues. Great to hear you found it. Thank you for using 2CarPros.

I'm having the same problem. Did everything from the other comments. I get no check engine light.

Have you used the LED test light to pull the codes? If not, that is the first place to start. If the CEL came on while driving there will be codes stored.

I have used the test light. No codes, no check engine light. I had to renew the head awhile back and I'm thinking a have the distributor in the wrong location. I've set it to 5* BTDC, but it runs like crap. If I set it to 8-10* BTDC it runs great.

Hi,

If you are able to get the distributor to the timing you mentioned, chances are that isn't the cause. When you replaced the head, are you sure the timing chain wasn't off a tooth?

Also, does it run poorly at idle? Have you checked things such as engine vacuum leaks and fuel pressure? If the poor running at 5 BTDC is limited to loading the engine, are you certain there isn't an issue with spark control (ignition advance)?

Let us know.

Take care.

Joe

Yeah. I double triple checked the timing chain placement. I have checked for vacuum leaks and fuel pressure. Haven't found any leaks and fuel pressure was with range. I have had numerous b2600i and have had to get the ECUs rebuilt in all of them. I'm thinking this ECU is still bad. Other than testing the ignition coil, I don't know of what else to check. Any ideas? Thanks

I'm also not getting any fault codes. The LED test light is working though. I've unplugged sensors and the fault codes come up for the sensor I unplugged.

Okay, you say you can set it to 8 degrees, and it runs fine, does it have any other issues other than the timing being off? No Check engine Light or loss of power or other issue? You are checking it with the test connector grounded, correct? If all of that is correct, I would bring number one up to TDC and verify that the timing mark is correctly on TDC with relation to the cover. Could you take a somewhat close up shot of the crankshaft pulley and post it on here? It's possible the outer ring has slipped on the rubber and that is the reason the timing shows as being wrong.

Its struggles with power on hard acceleration, seems like it's choking itself out. I have no fault codes. I have had to get the ECUs rebuilt on these trucks in the past and have had this one rebuilt. Here is the pulley, keyway is 1200 and the timing mark is at TDC.

Okay, just wondered if it may have slipped, have seen it happen a few times. Nothing like trying to set timing when the target is always moving around. Here's a test, you say bumping the timing up helps, try moving it a bit higher and then see if the top end power improves, if it does it would mean that the timing isn't advancing the way it should. What does the mark show if you rev it in park? Being a 1990 they generally don't set codes until things are really bad. Sort of like someone who won't go to the doctor for anything less than a torn off limb or a bullet wound, everything else is just "wear and tear" I've seen OBD I cars that never set a code but were barely able to run from all the things actually wrong with them.

The timing barely moves at all while revving it up, maybe 3 degrees. I was told by another mechanic, which means the ECU is still bad. That sound correct to you????

The timing not changing is likely the root cause as it needs to advance as the rpms rise, when it doesn't you get the issues, you have. That distributor should have a mechanical advance in it as well as the electronic system, from your description I would say the issue is the mechanical parts as failures in the electronics would set a code due to the timing being off, the mechanical parts however won't set a code as they are not monitored. It's also possible as you see no advance at all that it's a combination of both.

Great. I will have to look at the distributor. It's fairly new, I renewed it in the past year, I believe. Heck, if anything I'll put the old one in and see what happens. Thanks for all the assistance.

Hi,

I noticed it has been a couple of days since we heard from you. Has any progress been made? We're interested in knowing.

Joe

Got a new distributor in and there was no change. I sent the ECU back out to the company that rebuilt it for me. So, we'll see.

Hi,

Thanks for the update. If you can, let us know how things turn out for you.

Take care,

Joe

Will do. thanks

ECU rebuilder found nothing wrong with my ECU, they sent me a known working ECU. I double, triple checked the timing pulled the valve cover off to make sure the distributor was going in correctly. Same hesitation problem runs great at 12* btdc, still no check engine light.

Okay, as a recap, the truck starts and runs fine with the timing at 12 btdc, but it has hesitation and lack of power when you accelerate. Is that correct? You replaced the distributor and went through the ECU. The timing doesn't seem to advance though.
Fuel system has the correct pressures as well, correct?

Yes.

When you say hesitation, how long does it last? Is it short term like you step on the pedal, and it bogs a bit then picks up quick, or is it more step on the gas and wait 20 seconds or more for it to catch up? Those engines are not super powerful, but they still shouldn't lag a lot if things are working. The lack of timing changes still makes me think there is an issue with the advance but with a new distributor that shouldn't be the case.

It typically starts hesitating around 2,400-2,500 RPMs and goes away. I still think it's the ECU. I've bought another one and we'll see how it goes.

When you say it goes away, do you mean it hits that area of RPMs and then corrects itself or that it just gets worse from that point? What does it do if you put it to the floor? Does it hit the same point and stumble and recover or does it drop off? That is about the point that the timing should be advancing to compensate for the higher RPMs.

Going through the gears, it hesitates at 2,400-2,500 RPMs. I will get to third and floor it, it'll hesitate at that RPM, eventually it'll move past that RPM and quit hesitating.

It almost has to be ignition related to that description. Fuel flow would cause issues above that rpm as well and adjusting the timing wouldn't do anything for that. Does this one has a vacuum line to the distributor? That was around the time they removed it but if you have it, start the engine then disconnect it and plug the line, take it for a drive and see if it improves or gets worse.

No vacuum line on the distributor. I have tested the primary and secondary coil resistance and its within spec. The only thing left would be the igniter and ignition control module, but I have spark. I'm not thinking that's the problem.

Okay, you have the newer system where that is all controlled electronically. Wouldn't it be the coil, those start to fail you would see it start breaking up and just get worse as the rpms climb, it wouldn't get better again. That's the strange thing is it getting better after it acts up. It's a long shot but how about disconnecting the EGR and see if things change. If it was suddenly opening at that RPM it could cause problems that would go away as the vacuum dropped off.

It does not have an EGR valve.

Hmm, this is a 90 correct? It should have EGB unless it was removed.

It's a 1992 B2600i. There are four vacuum switches on the right side of the engine, before all this drama started i checked them and they were opening and closing with jumper wires, they are also getting 12-volts from the harness. Now the third one down won't open. I know these things have to do with emissions.