I have an '86 4Runner with a 22RE and about 80,000 miles on it.

I just replaced the headgasket on it (it failed causing an external leak from the water jacket down the side of the block -- nothing too damaging and serious). I checked all surfaces for straightness, so that front is good. The vehicle still ran perfectly before the headgasket change.

Since it has been reassembled, I have set the valve clearance once only (I may re-check, but I don't think that is my problem), set the timing properly, re-cleaned the distributor points and checked all connections, vacuum hoses, etc.

My problem is that the very first time I start the vehicle after it has sat for an hour or two (cold engine), the truck takes about 5 - 10 seconds of cranking the starter to finally turn over. Once it does, it is a little rough for about 5 seconds, then smooths right out to normal.

I jumpered the fuel pump tester on the driver's side front fender, and found that the return fuel line coming from the pressure regulator on the back of the fuel rail feels like it has lots of bubbles in it -- is this normal? While I had the intake off, I sent the injectors out to a local shop to be professionally cleaned.

The o-rings on the injectors couldn't be replaced, as my dealership couldn't order me the o-rings -- would this be causing my problem of hard starting by bleeding fuel pressure off?? Everything else (all gaskets) pretty well were replaced.

The vehicle also idles very low now (about 400 rpm) once warmed up, and, from a stop, when you initially press the gas, the vehicle bogs a little (by about 200 - 300 rpm), then takes off normally, and runs like a champ. I don't know if this is related.

If any of you have fixed a problem like this, I've searched, and have come up with nothing. Please let me know!


Thanks!

 

The o-rings are not reusable. So, if you're getting air in the fuel system and losing pressure...yes..that could be the problem. And, I'd suspect it was since the truck started and ran fine before the rebuild. Meaning, there is the cold start injection system that could be a problem with cold starts, but it worked before and probably does now.

Get some o-rings and replace them. Bubbles are not normal.

 

also get the idle speed up to where it should be when the engine's warm- 750-800.

 

I have this same problem on my truck and it's because the injector on cylinder 4 leaks all the pressure out as it sits overnight so it has to build that pressure up again when starting for the first time. I'm planning on fixing the leak this weekend.

Rob

 

Hey everyone,

Thanks for the replies,

I was told that were there a leak from the o-rings, I would definitely be smelling unburnt fuel. I felt around the injectors with the engine running (probably not too smart), and felt no fuel, and smell no fuel. This was told to me by the dealership who wouldn't order me o-rings for the injectors, however, so, I don't really give what they have to say much credit!

I was going to re-adjust the idle, as I know it is low (as others said, 750 - 800 rpm is the proper idle), but, I see it as almost a kind of band-aid solution to a problem, as it idled perfectly before. I'll be taking it up to a cottage this weekend, and won't have time to work on it until probably Sunday, so, if I end up taking it out of the city, I'll probably band-aid it just to tide me over until I end up changing the o-rings.

Were it to be my vacuum lines wrongly connected or cracked (I labelled every single one, but, you never know), the truck would constantly run like crap, right??

I was pretty sure I should've just gone to another dealership and ordered the o-rings at the time (the shop who "cleaned" the injectors were also a bunch of money grabbers and also wouldn't give me o-rings, but that's another story!). Now, I get to pay for new intake gaskets from the dealership.... again!!

Thanks again for your help, guys!

 

You can buy injector rebuild kits on eBay. You need something like this: http://cgi.ebay.com/ebaymotors/ws/eB...m=300224771043 I've bought from that guy twice.

Rob

 

I assume you've eliminated the CSV?

If you pull the connector on the TPS, does it run differently?

 

well the engine ran fine before the headgasket got replaced and now it doesn't so obviously something changed. could it be that the gasket had been leaking for a while and finally let go, but all that time when it was running good there was another problem and now that the engine has a good headgasket, intake gasket and the like, whatever was wrong is gone and the adjustments that made it run get then are not correct now?

now, if you are not seeing fuel leaking around the injectors' o-rings, i'd guess you don't have a fuel leak. 40 psi pressure will tend to make fuel leak around whatever it possibly can. so now, you probably don't need a new intake gasket set.

you've adjusted the valves so that's done, adjust the idle speed and timing... well you did half that... you do know that the timing changes with engine speed right? and that the timing spec on the decal under the hood (or in the service manual too) requires the idle speed to be correct? if the idle speed isn't correct the timing wasn't set properly.

sorry if you think I'm bustin your chops or something but I'm not trying to. read the pseudo-quote in my sig.

 

Couple things come to mind here;

- As you already know, never reuse o-rings. But since you're aren't leaking, I'll chalk you up to lucky.

- You can't get air in the fuel rail from a bad o-ring. The fuel system is suppose to be under constant pressure (even shut off). If the o-ring fails, you have a fuel leak.

- You mention the idle is quite low when it first catches. That's indicating a fuel deliver problem too. Here's my suggestion;

Confirm a fuel pressure problem; Attach a fuel pressure gauge inline of the fuel delivery tube. 2-4 hours after shutdown, view fuel pressure. If it is below half of normal operating pressure, you have an internal fuel leak.
OR!
You could wire a temporary switch to manually prime the pump. This can be done either at the pump wiring itself (if accessable) or by modifiying a spare fuel pump relay to accept an external trigger. Older Toyotas do not have a prime pulse when the key is cycled to "ON" like domestics. If you do either, and the truck behaves as it should when primed manually, you've confirmed a loss of fuel pressure while sitting.

Possible problem locations;

Leaking injector. You're losing your fuel pressure to an injector that's not closing properly. You could verify this by pulling all your spark plugs & inserting dry, rolled up pieces of printer paper into the plug holes. Let it sit for an hour, and pull 'em out. If one smells strongly of gasoline, you've found your problem.

Leaking return line. Use vice-grips to pinch the return line. Retest using procedure outlined above.

Leaking check-valve in sending unit. If no injector leak is found, and pinching the return line does not keep the pressure up, then it's fairly safe to say your pressure is dropping back through the valve in the sending unit.

 

Hey, thanks for the reply!

I'm going to adjust the idle speed along with the timing hopefully tomorrow. I'll let you know how it goes -- all I was sure of was that I was bleeding off fuel pressure from somewhere, due to the long cranking -- I would've thought that idle speed wouldn't have much to do with initial starting (when you start the vehicle up initially, it cranks for 5 - 10 seconds, but then it idles at the proper 750 - 800 rpm, just runs a little shaky for a few seconds).

With the diagnostic jumper shorted, to set timing, the vehicle idled REALLY low, so low I thought it was going to die -- maybe 150 - 200 rpm. I'm not sure if that throws a wrench in any previous ideas, but, I just remembered that tidbit!

I'll be sure to update the progress after the idle speed is set; we'll see if that helps!

If I have a leaking injector, I would assume the truck would run poorly even when the vehicle is running, no? The local place I took the injectors to was really really shady from the looks of it (they didn't even replace the green-coloured end caps on the injectors, which I was told they were supposed to). They also charged me about $150 -- but I assume I have no case with them if they did screw my injectors up!

I can't see the sending unit leaking, as the extent the fuel system was disassembled was that the intake system was removed, and the main fuel line (along with the return line) was disconnected during the headgasket change. The fuel rail was separated, and the injectors removed.

Just to clarify, it wouldn't really be possible to have a fuel leak which doesn't leak per se, but just lets the fuel pressure bleed off, without smelling fuel, seeing fuel spraying, etc, from the 40psi of fuel pressure? That was my only concern.

I'll definitely update as I keep checking things

Thanks again,
Yusuf