Car stalls while driving

Hello,

I have included in the diagrams down below the factory diagnostic troubleshooting guide for your vehicle's Exhaust Gas Re-circulation (EGR) system. It should help you pinpoint what is going on with your EGR system so you can get it fixed, and fixed right. Please go through this guide and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

What is the picture that says lock and my test lead is not yellow. Do you mean red? Procedure is hard to understand and follow.

Can you dummy down this procedure a little and be clearer on test leads? Mine are red and black as most are.

Hello again,

Sorry about that. The "lock" on the picture is simply showing the top of the electrical connector, where the two connectors "snap" together. It is just for reference so we know what is considered the top of the connector. Yes, yellow is the red, or positive, lead on your multimeter. A lot of vehicle manufacturers have fancier tools than us average guys have, and their positive leads are all yellow. Weird, huh? I think they do it on purpose just to be different.

Thanks,
Alex
2CarPros

That is what I thought the lock was, but I am not getting any vacuum to the EGR valve. All hoses are okay and connected. Today the car began stalling and upon a hard restart it would not go over 1,500 rpm without falling flat. New code was cam sensor and not shifting into second gear properly, 11 and 114 I believe they were. Car shifted fine and then started to run normal again close to home. If I hook the intake vacuum from the fuel pressure reg directly to the EGR the car stalls out. The BPT valve is fine as is the solenoid. I am baffled by this and I know I'll be stranded soon. This seems to only occur when there is barely any throttle and the car is very hot but the temperature gauge is normal.

Hello again,

Okay, after giving this some thought, I've come up with a couple more possibilities, but we can eliminate one right now. I have included in the diagrams down below a factory test for your vehicle's EGR BPT valve. Go through this simple test and get back to us with what you are able to find out. If the test confirms that the EGR BPT Valve is okay, then we might want to check and see if your catalytic converter might be partially plugged, but let's cross that bridge after we confirm or deny that the EGR BPT valve is working correctly or not.

Thanks,
Alex
2CarPros

I don't completely understand step 2. If I disconnect the line to the BPT and then connect the intake vacuum to the BPT how will the EGR lift? Which port do I connect the vacuum to on the BPT? Where do I get a 1mm restrictor? Isn't another test for the BPT to disconnect the lines from all three ports and blow in one of the top ones while plugging the other and feel no restriction out the bottom? I too suspected the catalytic converter but then it started running okay again, especially when cooled down.

Actually suck, not blow, on one of the top port and there should be no blockage.

Hello again,

I'm not entirely sure where to get a 1mm restrictor, my guess would be at your local hardware store. I know I can get connectors for vacuum tubes that run down to a 1/16", and that is pretty close 1/25" would be 1mm, at my local hardware store. Get back to us with what you find out.

Thanks,
Alex
2CarPros

The connection procedure is not clear and where is the canister control solenoid? Won't there be an open port on the top of the BPT? I still don't see how the link will be made to the EGR if the hose to the BPT is disconnected Can you show a diagram of this procedure please?

here are some photos. What is the red test lead pointing to? What is on the passenger side of the engine above the oil filter? It has at least four wires to it.

Hello again,

I am sorry but there is no diagram for this procedure. It sounds pretty much straight forward though, disconnect the vacuum hose from the fuel pressure regulator. Install a 1mm coupler/reducer in the vacuum line. Disconnect the vacuum hose from the BPT and connect the vacuum line from the fuel pressure regulator and test the make sure that the BPT is opening and closing at the specified RPM's. Let us know if the BPT is working correctly or not.

Thanks,
Alex
2CarPros

Don't you mean see if the EGR is lifting? That is what the procedure says.Again if you hook direct vacuum to the BPT but have disconnected the EGR how will the vacuum get to the EGR? Where would you connect vacuum to the BPT ? Where the canister line was?

Okay, I connected direct vacuum from the fuel pressure regulator feed to the canister port on the BPT and the EGR lifted when throttle was applied.

I ran direct vacuum to the BPT and left the line to the EGR in place. I don't know if this is what you meant or not.

Hello again,

Okay, so we can rule out the BPT as the problem. Lets check out the catalytic converter and make sure that it's not plugged or partially plugged and causing this problem. I have included a couple of links for you to go to below.

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms
https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Please go through these guides and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

I am not sure about the catalytic converter. If I measure temperature on the exhaust pipe going in and coming out it's different than if I point right on the front and the back of the catalytic converter chamber. The latter gives me indication that the catalytic converter is good , at least right when I pull in from driving and leave it run. I don't know if I'm supposed to measure it while running or not. The car is not down on power and they are currently no codes to read. I guess I'll drive it and wait for my next clue unless you have other ideas. If I try to loosen the flange or the O2 sensor I'm sure they will both snap. Rusty old cars as they are .

Hello again,

I have included a couple of links for you to go to down below. They are catalytic converter guides and will give you instructions on how to test your catalytic converters.

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms
https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Please go through these guides and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

I sent you a reply regarding the catalytic converter . There is a temperature difference right after I park and leave the car run to measure it. I haven't tried the other things yet. The car was running fine with no codes but today it acted up again. It lost power and when I floored it , it popped and cracked as if the catalytic converter was plugged and then ran fine again. I am at a loss as to what is really going on. How could it run normal and then act up if the catalytic converter is plugged? It seems to be fine unless I drive for extended periods of time stopping and starting several times. It is not running hot at all. Last time it did this there was a code for unable to shift into 2nd gear and one for the cam sensor? Also when driving at 1,000 rpm it seems to lug, almost feels like a transmission issue?

There were no codes showing but I checked anyway and it stored 11 and 127. Those are cam position sensor and engine speed signal. I'm going to see if there is oil in the distributor again.Any other ideas? Thank you for your assistance. More oil in the distributor, is Fel Pro 70015 the correct seal for the shaft. I'm getting differing answers, If I pull the distributor to replace the o ring do you have a video for checking timing ?

Hello again,

FelPro gasket 70015 is a fuel pump gasket that primarily fits domestic cars.

Thanks,
Alex
2CarPros.

I understand that but is it the same size as the o-ring on the distributor base shaft. If I pull the distributor to replace the o-ring do you have a video for checking timing?

Hello again,

I don't believe we have a video of how to do a 1996 Nissan Altima ignition timing, but I have included the step by step directions from Nissan in the diagrams down below. Please go through this guide and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

I did not check the timing or replace the distributor shaft o-ring.I did clean the cam sensor again. It seems now the car has to crank for three to five seconds before firing. I even need to press the accelerator slightly to get it to fire. When it starts it seems to run fine. It hasn't stalled for a while now. It usually only does during a lot of stop and go driving. I cleaned the MAF sensor with the proper cleaner and after that it fired right up . Then I drove it for about twenty miles and it sat for a couple hours and it was back to needing to crank and have the accelerator applied to fire. I would be interested in your thoughts on this. thank you for your assistance.

Did you try replacing the BPT? it could be shorted and when a command is giving it can shut down the ECM.

In earlier testing we ruled out the BPT and also the CAT for possible clogging. Any other ideas? Car runs fine just takes a tap on throttle to fire sometimes.

Have you serviced the throttle bore? It sounds like it is dirty. Vacuum leak?

Here are two guides that might help:

https://www.2carpros.com/articles/throttle-actuator-service

and

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Can you please shoot a quick video with your phone so we can see what's going on, that would be great. You can upload it here with your response.

I did clean the throttle bore it was a little dirty when I went to start it this morning I didn't need to press the gas but as you see in the little video I shot when I was leaving work I did need to give it some gas.

Thanks for the video, it sounds like you have a weak fuel pump or clogged fuel filter. Here is the fuel filter guide and location so you can change it with a guide to help you test the fuel pressure:

https://www.2carpros.com/articles/how-to-change-a-fuel-filter

and

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

At Idle With Pressure Regulator Vacuum Hose:
Connected .................... Approximately 235 kPa (34 psi)
Disconnected .................... Approximately 294 kPa (43 psi)

Check out the diagrams (below). Please let us know what happens.

I tested the pressure and I thought it was very low but your specs are different then those online. Other sites say 50 psi. Mine was about 35 and 45 respectively and I just changed the fuel filter very recently. The car will fire without pressing the accelerator after a few seconds. It's just easier to give a little gas. No engine lights and no stalling recently? Still at a loss but looking for a newer car anyway. I would still like to know what's going on here though.

35, 45 psi is too low, I would replace the fuel pump here is a guide to walk you through the steps with diagrams and instructions below to show you how on your car.

https://www.2carpros.com/articles/how-to-replace-an-electric-fuel-pump

Check out the diagrams (below). Please let us know what happens.