Hi. I have a 1994 honda accord lx wagon with 241,000 miles.
Automatic transmission.
The car usually starts right up without issue and idles around 2k rpm without the AC on. With AC on it idles around 1k rpm.
The car will lose power randomly while in gear and driving and also randomly while idling. The RPMs drop and it stalls/dies.
Here is a list of everything I've done to the car.
Installed new fuel pump.
Installed new fuel filter.
Installed new spark plugs.
Installed new spark plug wires.
Installed new battery.
Replaced distributor.
Replaced ignition coil.
Inspected all fuel lines and all vacuum hoses.
Inspected all grounds.
Checked each cylinder for compression and found them to be within specs.
Checked all fuses and relays and found them to be in good shape.
The car seems to run fine until the RPMs drop randomly and it dies. However, it will start right back up each time and if I put it in gear and give it gas quickly I can drive it again for a minute or so before it dies again.
If anyone has any advice I would appreciate it greatly!
-Chris
Clean the throttle body and mass air flow. On a 94 its a MAP sensor I believe. Here are links.
Alright I'll give that a try. Thanks!
Hey Chris, hello from California. You've got a good list of service records, are these all things that you have done yourself? Some vacuum leaks don't necessarily come from hoses but rather worn or faulty gasket materials. You would only really be able to find it after a very long drive hitting at higher RPMs. At this point all of those OEM bolts torqued to spec begin to show their wear alongside the gasket materials. I'm surprised these service records you included do not show the idle air control valve or air filter. IAC valves sticking can also cause cars to stall out at idle.
Hello! I should have mentioned that I'm a budding mechanic and am currently in college to get an associate's in automotive technician technology.
Many of the services performed on my car have been done at the college shop with supervision of my mechanic instructor. I had not thought about the idle air control valve. Would that also have the car losing power while driving at any speed?
When your throttle body is completely closed then you will receive very little to no air to the engine. The bypass that prevents the car from stalling out is the idle air control valve which feeds a set amount of air to the engine when you let off the gas pedal (and throttle cable). If it is sticking at a too closed or too open position then it could throw off the A/F ratio you are decelerating. My advice would be to test the throttle position sensor to see that it is giving a steady flow of resistance across full open and full closed positions. The next step would be to clean and lubricate the idle air control valve or replace it altogether depending on its age and condition.
Here is a good vid that explains testing of the TPS sensor, its not from scotty but from another well known mechanic youtuber.
https://www.youtube.com/watch?v=_skVHdgtMTU
Many thanks bud! Today I cleaned the MAP sensor and throttle body with CRC electronic spray cleaner and GUNK spray cleaner respectively.
I tried to remove the IAC valve and clean it but I couldn't get a wrench on the last bolt holding it on. I'll see about having a friend help me with that.
I let it dry for about 30 minutes and put the map sensor back on. Reattached the air intake and cranked it up.
The first two times I started it, I revved the engine to about 4k and it would drop rpm and die. After that I started it a third time and it revved all the way to red line around 7k and went back to idle at 1k. I let it idle for about 15 minutes and it didn't stall out.
Didn't get a chance to road test it since I have to get ready for work.
I will definitely look into the throttle position sensor and IAC valve and post the results.
Oh also wanted to add that we changed the air filter at the college shop. One of the first things we did and I forgot to add that to the service record list.
Hey good work man. Yeah those 90s hondas/toyotas are tanks. Save for the few electrical problems here and there they are super reliable. They are great cars for learning mechanic stuff on. Good luck
Many thanks! I'll keep working on it and post my results with every thing I try. It's been great experience for me, that's for sure!
Did you replace the distributor before or after these symptoms? These cars are known for having weak modules in the distributor.
After the symptoms.