So a couple of weeks ago I bought this four runner, I had to replace the water bypass line. After finding out everything I had to do I decided to replace timing belt and water pump as well. I had a leak at the injectors so I replaced all the o-rings which stopped the leak. I also replace the cold start fuel line. Now I have everything put back together and on a cold start it takes some starter fluid and about 20 minutes to get it going. When it finally fires up it stays with 3-400 rpms. When it warms up to temperature, I can shut it off and turn it back on with no issues. I am currently throwing 3 codes, both O2 sensors and the water coolant temp sensor. I know I also have a bad tvv valve. The vaccum hoses might have been on wrong as well so I'm looking up diagrams for those. I'm wondering if those could be a cause of a rough cold start, I can't think of anything else that would. Thanks for the help!

 

Welcome to YotaTech.

There are, oh, one gazillion causes of rough cold start. Vacuum leaks (or mis-routed vacuum lines) are only one of them.

Get your vacuum lines right. There is a sticker under the hood that is your saviour.

Check your ignition timing. Check for good spark at each cylinder. (also done with timing light). Check the cold start injector (gotta be pretty cold for that to be an issue. To check it, remove the CSI from the plenum without disconnecting the fuel line. Put it into a suitable container, and have your assistant crank it. The CSI only sprays while cranking, and when it's cold.)

 

you don't really need to remove the CSI, just back it out from the plenum enough to see the tip. when cranking (and cold enough) you will be able to see if it is spraying fuel, and the fuel will go into the plenum as long as you haven't pulled it way out..has the advantage of not putting to much strain (and cracking or kinking the line) on the hard line by pulling it out further to have it spray into a different container.

also, did the engine start normally prior to doing the repair work?

 

The vehicle started one time I drove it around the block within two minutes it shut off and didn't turn back on. The CSI was snapped so I had to replace that it also had a bad gas leak. I testing it, and It does work. I'm mainly assuming it's going to be the vaccum lines on wrong just wasn't positive if everything else could mess it up