Bogging down

Lets start by running the codes to see what the computer is telling us. Hear is a link to help:

https://www.2carpros.com/articles/odb1-isuzu-1985-1994-cars-and-trucks-code-retrieval-procedure-and-definition

Please run down this guide and report back.

My check engine light comes on and off a couple times a day. Then all of a sudden without warning I went out to start my vehicle and it will not run right. It idles funny and when I step on the gas it will not rev up. It sounds like it is bogging down. I had to tow it to my house because the top speed is like fifteen mph.

Hi littleroofer, Welcome to 2CarPros and thank you for the donation.

Check engine light on.

Have the computer scanned for code/s-you have a problem within the engine management system that caused the CEL to turn on. This is your starting point of diagnosis, finding out what is going on. We start here and comeback with the code/s.

I was coming back from a trip and it lost power and started to miss the last forty miles.

Plugs, coils wires are fairly new, (less then 1,000 miles). Compression check showed 180lbs except for the fourth and sixth cylinder, only 150lbs. No water in the oil. Car starts right up, just runs rough hot or cold. Blows out quite a bit of carbon when you first start it up. Average oil consumption for a car with that many miles.

I tried pulling plug wires to see if I notice any difference. Not much difference when I pulled six, car shut off each time I pulled three.

I checked for vacuum leaks, did not see to be any, unplugged choke, throttle body sensor, p to see if there was any real difference, just variance in idle speeds.

I do not know what other information I can give you.

Hello. Great information on the problem. Thanks. If I understand you correctly, 3 and 6 are the ones that give you the problem. Plugs 3 and 6 run off the same coil. I have attached the picture. The coil may be bad based off of what you say since they are on the same coil. If all the coils are the same which they look like, swap with the one next to it and see if the problem transfers to those two cylinders. That would show it is the coil. Also have you check for codes? You could go to Auto Zone or O'Rileys and for free they can pull the codes to the car. Most important. Once they check your codes, if they find something and you do not get it fixed and need to get back with us, please make sure you tell us exactly what the code was, number and all. Example, if the code was E0568 O2 sensor bad. Then make sure you give us all of that. While there for free also they can bring their tester out and check your battery, alternator and starter. I would also take a spray bottle of water and spray all over them while running and see if it acts up.

PURPOSE Provides high voltage necessary to ignite the combustion gas. OPERATION The electronic ignition system uses a waste spark method of distribution. For example, in this type of system the ignition control module triggers the #1-4 coil pair resulting in both #1 and #4 spark plugs firing at the same time #1 cylinder is on the compression stroke at the same time #4 is on the exhaust stroke, resulting in a lower energy requirement to fire #4 spark plug. This leaves the remainder of the high voltage to be used to fire #1 spark plug.

Will a O2 Sensor make the vehicle lose power going up a hill? While on the interstate I can have the pedal to the floor running 75 mph and it will loose acceleration to 60 mph. Also it smells like raw gas.

Hi claycfus,

Yes it can but diagnostics should be done to confirm if that is the cause.

Is the Check Engine Lamp indicating and have you tried to retrieve for trouble codes?

Hello, my car loses power when going uphill. It also tends to just stop (not quit running) if I am trying to back over a small bump (like a rut in the road) or back uphill. I push down on the accelerator and nothing happens the engine doesn't rev, the tachometer stays constant. The car starts fine and the engine sounds fine, and it runs okay on flat road surfaces. But as soon as I try to go uphill, I just lose speed. The tachometer stays the same or may drag down a bit. It has a new timing belt, fuel filter, transmission filter, and TPS. I am kind of thinking the ECM is the next likely suspect, but I do not know how to test it? Do you have any suggestions on what else it could possibly be? The vacuum was a bit low at 12-13 lbs. However, when a propane tank was put near the vacuum lines, nothing happened, so no detectable vacuum leak. There are no codes being set.
Thank you for any suggestions. :)

Scan for codes and check fuel pressure, but with vacuum at 12-13 psi at idle check for a clogged exhaust like a catalytic converter problem.