1995 2.7l Won't start, has fuel and spark

Hi, I am new to Tacoma World, and my reason for joining is my very frustrating no-start situation with my 1995 Tacoma. I have 320,000 miles on it, and have not had any engine issues until now. It was time for a tune-up, and I put new plugs, wires, distributor cap, and rotor on. I drove it for about a week and it ran fine until a rainy day when, while I was driving it, it started to sputter, as if it was low on fuel. The tank was half full. I kept driving it for about 7 minutes and it started sputtering worse and worse until it eventually sorta backfired and quit. I immediately pulled the plugs and checked for spark, and I had it on all 4 plugs. When I pulled them out of their holes, they were soaked with fuel, and I could smell fuel. I got towed home and since then have changed the fuel filter, the coil, checked compression, timing, fuel pressure, and I have double-checked the spark countless times, and can find no reason for it to not start. There had been a light on for the MAF sensor and IAT sensor for a couple weeks, and I bought replacements for both of those but they did not help. It did randomly start one day, ran for several minutes, and then died in the same manner as before, sputtering until it just quit altogether. But other than that I have been unable to get it started on starting fluid. Every time I pull a plug out, it is soaked in gas, and every time I check for spark on that plug, it has a good strong spark. Maybe it is not sparking inside the engine for some reason, I don't know. I'd appreciate any help.
Thanks!

 

You have spark and fuel. Do you have compression?

 

Yes I do. 155 in 1,2,3, and 160 in 4

 

Does it run if you unplug the MAF?

 

No, I have tried multiple times with it plugged and unplugged, and I even replaced the MAF sensor

 

At this point you may be flooded. Maybe try pullimg the fuse for the injectors, pull thr plugs and spin it over a few times. Dry the plugs and reinstall them and fuse. See if it will start. Won't fix root of problem but might help in finding it if it will start.

 

Dude, same issue with my 03 at 292k miles after having no engine problems to speak of. Replaced TPS, CPS, remanned the ECM, MAF is fine, all that. It’s gotten so frustrating I’m selling it, tbh:

https://www.tacomaworld.com/threads...-4x4-tacoma-on-recall-frame-6-000-obo.839844/

 

Btw, one thing I had to do that you might as well is to change the oil after all that flooded fuel sits in your cylinders and runs down into the pan.

 

I’ll guess spark plug tube gaskets.

 

I would stick in a new(used) open circuit relay....

even if that is not it.......its not bad to carry a spare

considering how important it is...


You can test for a bad crank sensor by jumping that same plug for a constant pump run....and try starting it.

that crank sensor pigtail can get oil soak, and is easily damaged

if runs with that plug jumped that means the CS or the open circuit is wore out...

maybe try to clean that sensor plug connection

 

Check your exhaust 02 sensor. Everytime I would pressure wash the engine bay my truck would sputter and stall. Had it happen once on a trail after going through a large puddle too. It would take 30-40 minutes before it would run right again. I found that I had an exhaust leak and water was getting in the exhaust right before the 02 sensor and fouling it out.

 

Thanks for all the advice. I did try taking out the plugs and drying them before putting them back in, then disconnecting the fuel injectors and using starting fluid instead. That didn't work either. Today I did a smoke test to see if there was a vacuum leak, and I found one at the egr valve vacuum solenoid, but I don't know what that means. The EGR valve is not stuck open.

 

I am getting plenty of fuel to the cylinder, and my fuel pump runs fine, and I tested my crank sensor at the pigtail and it read fine.
If the open circuit relay is bad, that would mean I would get no fuel to the cylinders at all, right?

 

What about a failed FP regulator?

i.e. dumping fuel

any codes?

 

Had a similar experience......when I pulled the fuel reg return line and crank it would spew

I changed the open relay and worked for a week....then no start

Later I found the old coils in the old open relay was leaking goo down into that plug connect....

I cleaned all that up with lots of electronic cleaner and stuck in a new open relay...


Same time I stuck a new denso crank sensor I had.........and started right up...


That was about 80 starts ago........all those are connected together.....and much more likely than spark problems.....



I figure I'll never have to worry about crank sensor ever again.......and I keep an extra open relay in glove box now........and an extra start switch

 

The fuel pressure regulator was checked and it works. There does seem to be a lot of fuel in the cylinders though. And the only codes I have are for the MAF sensor and the IAT sensor, both of which I replaced.

 

How about your throttle position sensor? Mine went out on similar situation but didn’t throw a code

 

Sounds like the timing is 180 degrees out.

 

Step 1, flash for codes
Step 2, with everything assembled put the gas pedal flat on the floor and crank it for up to 10 seconds and see if it starts.

if it starts, does the engine sound progressively more laboured until it dies?
If it does then i'd bet you have a plugged cat based on the fuel impression i'm getting of raw fuel in the cylinders. The raw fuel will combust in the cats and melt the catalyst. Removing the O2 sensor upstream of the cat and attempting to start the truck is a quick and dirty way to diag a plugged exhaust.... it will be very very loud... wear ear plugs at the least.

If you have a plugged cat then you'll have to diag and repair the cause of the excess fuelling before replacing the cat or you're gonna run into the same issue again.

If you didn't use an OEM maf then I wouldn't rule it out as being bad... aftermarket parts nowadays are extremely grey in quality... other possibilities are a sticking fuel pressure regulator, leaking injectors or defective ignition components that fail when they are under the load of a running engine vs making it spark into the air

If the truck seems to not start after all of this then run another compression test. I've seen cylinder flooding cause the rings to not seal and cause the engine to have no/low compression. If that's the case then a little oil in each cylinder and cycling the engine will bring back the compression to normal.

 

Update for my truck's situation:
My cat isn't plugged.
I let it sit for several days with the plugs out and didn't try to turn it over or anything. Then after several days I just turned the key and it started right up. It idled normal for about a minute until it started a tiny miss every once in a while at idle, I kept hearing the miss and it ran for about 10 minutes. Towards the beginning, I could rev the engine and it would run smoothly, but towards the end of it started to run rougher, and when I hit the gas it stalled out completely and hasn't started since. However I still am getting spark and gas to the cylinders. This is the third time this pretty much exact same thing has happened since it stopped running originally. At least it's a pattern now. Any ideas?