Vanman

Related?

History: Truck has been running fine. Plowed with it last night, no issues what so ever. Just had oil changed last week.
Last night we had a blizzard, snow got into the garage (long story) and blew around the vehicle enough that I had to brush it off!

Today I went out to plow, the truck took three times to start (always starts first attempt even when sitting out at work all day in the winter). Ran really rough, never got better.

Things I noticed:

Only after running it for 10 minutes or so, did the oil pressure indicator go to the low line (line between low and normal), then a bit under. I shut off the engine, oil level as far as measured with he dipstick is full.

There is a little fan in front of the radiator that was not moving at all. It was packed with snow. I unpacked it, got it so it would rotate, but it would still not run when engine was on.

Did I get snow in somewhere where snow ain't supposed to be? The engine has 155,000 miles on it. It was just at the dealer (there is the problem!) last weekend for break line work (funny, the had just flushed the line a month before the breakline busted) and an oil change. I generally trust this dealer.

Just wondering where to start. The only other thing I can think of is that I pushed this elderly man and his pickup truck 1.5 miles to his house the other day (he was broken down on the side of the road).

Thanks in advance.

DeathCougar

iTrader: (23)

The small electrical fan in front of the engine is for the AC. That will not turn on until you turn your AC on...which one would hope you don't do during the winter lol.

Vanman

OK, so a neighbor told me to check the filter, etc. Did that, but where is the actual air intake? Could that be clogged with ice/snow?

Thanks

ahickman

Someone correct me if I am wrong, but the oil pressure would drop after 10 minutes owing to the lower viscosity as it heated. My 22RE and 3VZE start at half way mark and then drop to 1/4 mark after it warms up. Field service manual (FSM) says it only need 4 PSI or above to adequately lube things up. Do you know where the oil level on yours normally (before you changed the oil) sits at idle and running speed?

The rough running condition could be a vacuum leak, bad plug or bad fuel. Have you changed your fuel filter ever? Check for vacuum leaks along any of the plumbing going to and from the intake/throttle body. Also check for leaks around and along the air intake (big tube going from the front of the driverside to the throttle body. Make sure there are no cracks or the clamps have not come loose at either end.

Vanman

I am wondering because it was running fine yesterday. Not that something can't just go wrong overnight. It is always above the low mark on the gage. Today it was on the mark, if not just a bit under, where it has never been before. It does fluctuate, just not to where it was today. As` I stated, I have never had problems starting it, and it took three times for the engine to run enough to keep going, then it was very rough.

It was exposed to loots of blowing snow, etc. That is why I was wondering about the air intake, as my neighbor had suggested. But where does the air first get into the engine system. Obviously it is before the filter. I want to see if there is something clogged with slow/ice.

Thanks.

ahickman

Here is a link to the FSM:

http://personal.utulsa.edu/~nathan-buchanan/93fsm/

and a link to the layout of the air intake and emission control:

http://personal.utulsa.edu/~nathan-b...74layoutan.pdf

You could unlatch the canister containing the air filter and remove the filter allowing ample air to hit the VAF and throttle body. If it runs better, you would be correct in that something is constricting the flow.

If not this, check the items above and then move on to things like checking the TPS and VAF with a volt/ohm meter. Maybe a description of how it idles and runs rough would be helpful?

Vanman

Thanks for the links. I haven't had time to go out and do anything yet.

The RPMs at idle are around 500-700 or so. Very low idle, almost stalling. The weird thing is that when I gave it gas, it "seemed" to be on the smooth side (as opposed to the very rough idle). Not misfiring, just rough.

Vanman

So I let the thing just sit for a few days. I has finally warmed up a bit, although no melting has gone on in my garage. I looked things over again, and the air filter seems OK. There is a tube/hose going into the filter from below, which seems to be where the air comes from, going to the filter. The funny thing is this seems to be attached to the rear of the headlight assembly (???). That is where I would have had snow packed in. Anyway, to make a long story short, I decided to start her up, and she seems to run fine.

Anything I should worry about at this point, other than to try to avoid packing snow up int he left side under/behind the grill?

Thanks for the input.

abecedarian

Snow accumulation blocking the air intake (behind the headlight) could cause idle issues.
As for the oil pressure... if the engine isn't running the the proper rpm's (i.e.: idling lower than normal, for instance due to restricted air intake) the oil pressure will be low as well.

with regards to oil (ahickman) a 5w30 oil behaves as a 5 when cold and a 30 when warm so the oil will tend to thicken as it warms up.