Notices
86-95 Trucks & 4Runners 2nd/3rd gen pickups, and 1st/2nd gen 4Runners with IFS

Is it my cold start injector time switch?

Old 12-13-2010, 03:35 PM
  #1  
Registered User
Thread Starter
 
hermyboy3000's Avatar
 
Join Date: Feb 2010
Location: Denver
Posts: 43
Likes: 0
Received 0 Likes on 0 Posts
Is it my cold start injector time switch?

My rig is really hard to start or it won't start at all when it's cold. If I squirt starter fluid into the air intake hose my truck will stumble to a start.

I checked my cold start injector time switch as described in the FSM. I think its shot, but before I drop the bucks for a new one, I want to verify that Ichecked the CSI switch right.

I set my meter to 20k ohm, and the meter read .08. The coolant temp was well over 100 degrees fahrenheit. according to the FSM if the coolant temp is over 77 the CSI resistance should be between 70~90 ohms. So is the ".08" reading on my meter 80 ohms? Sorry about the noob question.

Thanks guys!
Old 12-13-2010, 04:36 PM
  #2  
Registered User
 
myyota's Avatar
 
Join Date: Oct 2006
Location: GrangeVille, Idaho
Posts: 4,166
Likes: 0
Received 8 Likes on 8 Posts
Most likely the cold start time switch is bad, they do wear out. I would recommend that you pull the cold start injector and clean it, they get carbon build up on them from the EGR and that can plug them up. Have you checked the cold start injector to make sure its good ?.
Old 12-13-2010, 08:41 PM
  #3  
Registered User
 
scope103's Avatar
 
Join Date: Sep 2007
Location: San Francisco East Bay
Posts: 8,250
Likes: 0
Received 820 Likes on 648 Posts
".08"k ohms is 80 ohms, but I've never seen a meter that would make you work that hard to figure out the scaling. So you might want to read up on your meter.

Better yet, consider pulling the injector out of the plenum, but leaving the fuel line (flex hose) and electrical connected. Put the injector into a glass jar with a rag over the top (it might splash), and have someone crank it. Does the injector spray? That way you'll have an end-to-end test. If it doesn't spray, you can work backward checking the electrical, the fuel connection, the injector itself, etc.
Old 12-14-2010, 09:59 AM
  #4  
Registered User
Thread Starter
 
hermyboy3000's Avatar
 
Join Date: Feb 2010
Location: Denver
Posts: 43
Likes: 0
Received 0 Likes on 0 Posts
So the CSI switch is reading within spec. . Does that assumption sound right to you?

Do I need to buy the special wire harness from Toyota to run the test on my cold start injector or is there a way to jimmy-rig it?

BTW, do you guys have a photo showing where the injector is on a 3vze?

I'd like to check the resistance while it's on the truck before removing it. One more thing, the FSM states that you can't reuse the gaskets on the injector, are the gaskets something easy to get?

Thanks!
Old 12-14-2010, 10:13 AM
  #5  
Registered User
 
scope103's Avatar
 
Join Date: Sep 2007
Location: San Francisco East Bay
Posts: 8,250
Likes: 0
Received 820 Likes on 648 Posts
If all you want to do is test the continuity of the injector, you don't need a wire harness. Just pop off the connector (it has a lock wire) and the pins are exposed.

The gaskets are aluminum, and cost about a buck each at the dealer (you'll need two). I think they are "pure" aluminum, and crush has you gently torque them down.

Some folks get away with reusing old ones (I have to admit that I've done it once or twice), but you're dealing with gasoline and a leak would be a "bad thing."
Old 12-14-2010, 12:45 PM
  #6  
Contributing Member
 
Marc's Avatar
 
Join Date: Sep 2003
Location: Winnipeg, MB, Canada
Posts: 1,241
Received 13 Likes on 13 Posts
Originally Posted by scope103
Better yet, consider pulling the injector out of the plenum, but leaving the fuel line (flex hose) and electrical connected. Put the injector into a glass jar with a rag over the top (it might splash), and have someone crank it. Does the injector spray? That way you'll have an end-to-end test. If it doesn't spray, you can work backward checking the electrical, the fuel connection, the injector itself, etc.
Have you done what scope103 suggested?
Old 12-14-2010, 02:28 PM
  #7  
Registered User
 
waynesworld's Avatar
 
Join Date: Mar 2010
Location: hampton virginia
Posts: 143
Likes: 0
Received 0 Likes on 0 Posts
hey i wouldn't recommend putting starting fluid in a engine .try sum wd-40.
Old 12-14-2010, 03:08 PM
  #8  
Registered User
Thread Starter
 
hermyboy3000's Avatar
 
Join Date: Feb 2010
Location: Denver
Posts: 43
Likes: 0
Received 0 Likes on 0 Posts
I did the test for resistance like the FSM describes, I got no reading. Is it safe to assume that the injector is dead, or should I still pull it and test it like scope recommended?
Old 12-14-2010, 06:23 PM
  #9  
Registered User
 
scope103's Avatar
 
Join Date: Sep 2007
Location: San Francisco East Bay
Posts: 8,250
Likes: 0
Received 820 Likes on 648 Posts
You tested the resistance of the injector (not the cold start time switch), and got "open"? (I never know what people mean when they measure resistance and get "no reading." Zero is a reading. Infinite (open) is a reading.) The correct resistance is only 2-4 ohms, and the leads alone on my fancy 4 1/2 digit ohmmeter have 1.7 ohms. So the FSM test is not easy to do correctly.

If you actually got "infinite" ohms then the injector is gone. Since it is a $150 item, I would be tempted to do one more step. You're removing the injector anyway. Once it is out, put 12v on the two terminals and see if you can hear anything (listen closely). If you can, hook it back up the fuel line. Use the FP connector in the diagnostic plug to pressurize the fuel system, and put 12v on the injector again to see if it sprays. If your FSM test was correct, you should hear nothing, and you should get no spraying. Then you can spend the $150 with a clear mind.
Old 12-15-2010, 06:16 PM
  #10  
Registered User
 
myyota's Avatar
 
Join Date: Oct 2006
Location: GrangeVille, Idaho
Posts: 4,166
Likes: 0
Received 8 Likes on 8 Posts
Originally Posted by hermyboy3000
I did the test for resistance like the FSM describes, I got no reading. Is it safe to assume that the injector is dead, or should I still pull it and test it like scope recommended?
If the cold start injector is bad, instead of buying a new one call Yota Yard, there a toyota wrecking yard in Denver and see if they have one.
Old 12-15-2010, 10:47 PM
  #11  
Registered User
Thread Starter
 
hermyboy3000's Avatar
 
Join Date: Feb 2010
Location: Denver
Posts: 43
Likes: 0
Received 0 Likes on 0 Posts
Scope, I got all zeroes in my test of the cold start injector, not infinite.

My yota, I completely spaced yota yard! Thanks for the reminder!
Old 12-16-2010, 06:26 AM
  #12  
Registered User
 
scope103's Avatar
 
Join Date: Sep 2007
Location: San Francisco East Bay
Posts: 8,250
Likes: 0
Received 820 Likes on 648 Posts
The spec is 2-4 ohms. Are you sure your ohmmeter can measure that small a value? If you're on the 1k range only 1% error will swamp that reading. (and if you're using an analog ohmmeter, well ....)

I'm no expert on injectors, but my guess is that they are more likely to fail open than shorted. Before I paid $150 or picked up a mystery part from a junk yard, I'd do a functional test of my own injector, using any of the ways I described.
The following users liked this post:
Jweiss7939 (03-15-2020)
Old 12-16-2010, 11:08 AM
  #13  
Registered User
Thread Starter
 
hermyboy3000's Avatar
 
Join Date: Feb 2010
Location: Denver
Posts: 43
Likes: 0
Received 0 Likes on 0 Posts
Scope, I'm using a digital meter on the 20k setting. But, I'm planning on doing the function test this weekend. So far it's been starting "rough"without the starting fluid.
Old 12-16-2010, 12:31 PM
  #14  
Registered User
 
scope103's Avatar
 
Join Date: Sep 2007
Location: San Francisco East Bay
Posts: 8,250
Likes: 0
Received 820 Likes on 648 Posts
LOL! What's the smallest resistance you can measure with a 3 1/2 digit digital meter on the 20kohm scale? A reading of 0001 is 10 ohms! So of course you got 0000 when you tried to measure 2-4 ohms.

Try an electrical test (like put 12v on the terminals and listen); it will be easier to do.
Old 12-19-2010, 05:16 PM
  #15  
Registered User
Thread Starter
 
hermyboy3000's Avatar
 
Join Date: Feb 2010
Location: Denver
Posts: 43
Likes: 0
Received 0 Likes on 0 Posts
Scope - you're probing of my testing technique made me take a closer look at the meter. I have a setting that goes 200 ohms, this gave me a reading of 5.6 on the cold start injector. So, thanks for second guessing my results! I also did the test you recommended, I did get the injector to squirt.

Anyhow, I found an injector at the junk yard that is within specs, I installed it today. So, I'll let all of you know how it goes tomorrow.
Old 12-30-2010, 07:31 PM
  #16  
Registered User
Thread Starter
 
hermyboy3000's Avatar
 
Join Date: Feb 2010
Location: Denver
Posts: 43
Likes: 0
Received 0 Likes on 0 Posts
Wink

Alright, been over a week since I installed the "new" injector the truck starts up, it's not an instant start, but it's quick enough!

Thanks a lot for all the help!

Last edited by hermyboy3000; 12-30-2010 at 07:33 PM.
Old 11-09-2020, 04:31 PM
  #17  
Registered User
 
prowe's Avatar
 
Join Date: Nov 2020
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
cold start injector sprays, but still no start

Hey all, my 1992 Toyota pickup stopped starting in the mornings when it got cold. When it warmed up to around 70 degrees outside, it would start fine. I removed and cleaned the injector, then hooked it back up to the fuel line and checked the spray when I cranked it. The spray checked out good. I put it all back together and the engine started and ran great. I turned it off, then tried to start it 20 minutes later and it wouldn't start. It hasn't started since. I don't think it could be the cold start sensor switch because it sprayed fine. I am stumped as to why it doesn't start now.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
serenity03k64
86-95 Trucks & 4Runners
0
06-27-2015 07:59 AM
jmc88runner
86-95 Trucks & 4Runners
3
06-18-2015 03:39 PM


Thread Tools
Search this Thread
Quick Reply: Is it my cold start injector time switch?



All times are GMT -8. The time now is 06:12 AM.