meridianfrost

Hi there. I can barely muster the energy to write this post, but I am going to give it a shot.

2 months ago I purchased a 1994 Toyota 4x4 DLX regular cab, and I have been working on it ever since. It was lifted when I bought it, but I didn't particularly care for the lift, so I removed it. That was an ordeal in and of itself. New shift levers, new steering wheel hole cover, relocated the radiator, removed and reinstalled bumper.

The truck had some of the worst hack job body work I had ever seen. I repaired that.

My problem is that the idle surges, and it is driving me insane. I have flushed the coolant, replaced the thermostat (was apparently faulty), replaced iffy vacuum lines, checked trottle body and coolant union on thermostat housing for blockages. None. Idle still surges.

When I crank it up from being cold, it does not surge. The cold idle seems to be working. When it begins to warm up, that is when the idle begins to surge. If I press the brake, the idle decreases dramatically, and surges while the brake is depressed.

A new development today is that the heater no longer work. The lights being turned on causes the truck to struggle to run, as does turning on the heater, as does running the windshield wipers.

Fresh coolant today, fresh oil today, new thermostat today, new throttle body vacuum lines today.

If there is a blockage somewhere, I can tell. All of the coolant lines I can find are all warm, and I know that it is being circulated. I'm just....at my wits end. I actually had the mental image of activating a timer on a cartoonish bundle of dynamite, and just chucking it over my shoulder into the cab of the truck and walking away.

Any help anyone can give me would be most appreciated.

Thanks in advance.

-meridian

HighLux

Surging idle when braking is a sign the idle itself is set to high.

I bet the timing is off...which made it idle low...so some one turned the idle screw to compensate.

Sturmcrow

Surging is often a sign of air in the coolant. It just takes a small bubble. Many guys find that jacking up the front of the truck while adding in the coolant helps get that last bubble out.

The bad news is that if you can never get that last bubble out, you might have a head gasket that is leaking exhaust into the cooling system. My old Civic does that, and has been doing it since 2007 or so (not worth fixing, and hasn't completely let go yet).

You can check for exhaust in the cooling system by watching for bubbles coming out of an open radiator cap (once you fill it all the way up). There are also testers that can evaluate if you have exhaust in your coolant reservoir bottle.

The decreasing idle when you hit the brakes is likely due to a leak within your brake booster. They are about $150 new online. A few weeks ago I posted the procedure for checking that, you could search for brake booster leak.

Innocent Fool

I'm assuming it's a 22re.

Mine did the same thing. Sometimes it would surge and have no heat, other times (even the same day) the idle & heat would be fine. Tried the idle adjustment method but no change. Ran it like this for two years. Found out what it was when the head gasket finally blew and I tore it apart. Turned out it had a slow leak and was pushing air into the coolant. Previous owner had used an aftermarket head gasket when he rebuilt the engine...

Hope you have better luck than I did

Terrys87

iTrader: (1)

Jack the front end up high and let it idle without the radiator cap to get the air out of the system. It is called burping the system. When I do mine, I have the radiator cap about neck high and I am 6 foot tall. It is up in the air.

ironlung

Charge your battery lately? I've noticed my 22re acts out when the battery gets weakened.

ksti

The most important thing you left out is, what motor your rig has.
You said new problem, heater in-op and runs bad when lights on or/and wipers.
This is what I would check:

(1) Battery Voltage
(2) Loose Alternator belt
(3) All ground straps for corrosion/dirty connections, bad grounds cause them to ms-behave also.

Check for any possible stored codes also.
Good Luck

P.S. Please respond back if you find out what it is so others can benefit.

Fundy Rider

In the exact same boat but except my head gasket has blown. All the symptoms you describe I have went through until the day I was dreading.

Bought it with a rebuilt motor (94 22re) and a good base for an expedition build. Only drove the thing 250 miles before it blew.

Decided to do it myself to get to know and learn about the truck. No mechanic by any means.

Four months later I am still at it. Mind you it has been cold this winter and left the block waiting for it's head until it finally warmed up.

Replaced and painted a lot of stuff to keep me positive about the project in the meantime.

At times I wish is was gone from my life as well but then again it is the tool I wanted and they don't make them anymore as todays trucks are getting soft and way out of my price range.

I know the day I'll be cruising down the road it will be epic. So stay positive since it's the only way to be or otherwise it will make you a cranky bastard. Ask me how I know?

Good luck!!!

wyoming9

iTrader: (1)

Maybe they will be back so many things we have no idea of.

I would like to know if there is a pattern to the idle going up and down like the AC compressor cycling when in defrost mode.

Without knowing what engine I know the 22R series lose heat if the coolant is to low all the changing of Coolant and no mention of bleeding

As mentioned low system Voltage can cause strange things to happen in the ECU.

Is it a fuel or electric problem no mention of changing fuel filter

muddmadness

Only mine only does it when the truck is cold and the clutch pedal is pressed down...the other day I was at an intersection and the idle went up so high the heater core hose blew off the back firewall. Scared the you know what out of me. I pulled over at a gas station(lucky there was one on the corner) replaced the hose refilled the radiator and burped with the hoses as best I could and took the truck directly home. Once the truck warms the idle surge is definitely quiets down. Weird and a pain in the butt...I haven't driven my truck since then. I don't know what to do, Haynes says it might be the valve clearance and it might make sense. The truck got a valve adjustment and it hasn't sounded right since. I wish I could figure it out...