Huge problem with intermittent starting... More in description thanks for reading!

Problems

New Member
Nov 23, 2019
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0
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2003 RWD Toyota Sequoia automatic transmission limited

The truck sometimes turns on other times you just hear the starter turning the engine over and nothing. When the engine actually turns on it works as it should perfectly no hiccups, NO ENGINE LIGHTS or any lights for that matter. I have changed the fuel filter and position crank sensor. Nothing. When she is turning over I check for spark and i get no spark, I check for fuel injection pulse and get no pulse. I have a feeling this is a computer problem but there is no way to diagnose because there is no codes! super frustrating..... I don't know what else to do. It is worse because this is my wife's car and she is always with the children. She has been almost left stranded a handful of times already. Sometimes it sounds like the battery is going to give and it finally turns over thankfully. I don't know how much longer this is going to last and I am worried. Thank you all for reading this!
 

Trideyota

Member
Dec 31, 2017
78
7
8
Telluride, CO
I had this problem when my wife was driving our 2002. She would call and say it would not start and I would show up and use my key with no problems. Turns out the after market key she was using had went bad and would only work sometimes and the key I used was the master and always worked. So I purchased a key off amazon and programmed it myself at a cost of $9. You can find the programming online.If it doesn't work the first time keep trying. It sometimes takes a few times to get the key to work.
 

Problems

New Member
Nov 23, 2019
6
0
1
31
I had this problem when my wife was driving our 2002. She would call and say it would not start and I would show up and use my key with no problems. Turns out the after market key she was using had went bad and would only work sometimes and the key I used was the master and always worked. So I purchased a key off amazon and programmed it myself at a cost of $9. You can find the programming online.If it doesn't work the first time keep trying. It sometimes takes a few times to get the key to work.
Thank you very much for this. This SUV was bought used and the keys are all aftermarket. (the type you have cut at homedepot or ace hardware) I don't have any originals, I don't think that these keys have chips in them or anything like that... Also the alarm system is an after market VIPER system. I will however do what you said and try to buy a key and reprogram it. If you have links to anything where to program and what key to buy I would greatly appreciate it! Thanks again!
 

Trideyota

Member
Dec 31, 2017
78
7
8
Telluride, CO
There is a chip inside the keys for the vehicle that communicates with the computer and security system. If you do not have the original Toyota master you can not program yourself. Good Luck!
 

Problems

New Member
Nov 23, 2019
6
0
1
31
There is a chip inside the keys for the vehicle that communicates with the computer and security system. If you do not have the original Toyota master you can not program yourself. Good Luck!
So I am guessing I would have to go to toyota stealership?
 

Trideyota

Member
Dec 31, 2017
78
7
8
Telluride, CO
Our went on forever before figuring out the problem. One of my coworkers was a master toyota tech, so I picked his brain on the issue and he said I remember something like this happening before. Made a few calls to the dealer he once worked at and everyone agreed this was more than likely the problem. My wife got a new Lexus 460 out of the deal, since she travels with the kids ans was tired of not knowing if her truck was going to start. I drive it now and have had no more problems.
 

Problems

New Member
Nov 23, 2019
6
0
1
31
Our went on forever before figuring out the problem. One of my coworkers was a master toyota tech, so I picked his brain on the issue and he said I remember something like this happening before. Made a few calls to the dealer he once worked at and everyone agreed this was more than likely the problem. My wife got a new Lexus 460 out of the deal, since she travels with the kids ans was tired of not knowing if her truck was going to start. I drive it now and have had no more problems.
After you told me this I am thinking that it is the ecu immobilizer.... The keys that I had cut never went through a program or anything it was litterally showed the guy the key he found the copy on the rack and cut it.... No special machine for programming or anything went on in that transaction... but who knows maybe I am wrong. I think I may look for a new car because I don't want to spend the money fixing this thing....... but IDK maybe I will. I went through th ehouse looking like a wild man for the master key maybe I had it but it was a no go.
 

Johnsonman

New Member
Nov 25, 2019
4
1
1
58
So it starts most of the time, so key is good. Have you read the odb2, regardless of whether a CEL light is on, it may have a pending code (not set yet but on the way)? If you don't have an odb2 reader, go to auto zone or like place, they'll read it for free.

I'd suspect a throttle position sensor or crank sensor if no spark at a times. If either sensor goes out intermittedly, the ECU won't get a signal to supply spark or fuel. Luck and enjoy the Sequoia.
 

Problems

New Member
Nov 23, 2019
6
0
1
31
So it starts most of the time, so key is good. Have you read the odb2, regardless of whether a CEL light is on, it may have a pending code (not set yet but on the way)? If you don't have an odb2 reader, go to auto zone or like place, they'll read it for free.

I'd suspect a throttle position sensor or crank sensor if no spark at a times. If either sensor goes out intermittedly, the ECU won't get a signal to supply spark or fuel. Luck and enjoy the Sequoia.
Thanks for the response. I changed the crank sensor and nothing. It turns on everytime but sometimes it take 1-5 times to turn on and the times it doesn't turn on there is no spark or no pulse on the fuel rail. I guess I am just going to have to live with it beacause there is no lights and nothing pending on the obd2....... Really sucks not knowing.....Maybe the throttle posiution sensor I don't know where that one is though....