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Hi my name is John I just bought my first Toyota car I've ever owned it is a 91 Toyota MR2 with a J spec engine Turbo.
Unfortunately I didn't get to do the swap myself. So I'm jumping into someone's project.
As far as I can tell they did a very good job everything seems to work properly except the engine running.
It takes a lot of cranking to get it to start up and when it does startup it is puttering skipping
And will not rev up at all if I feather the gas pedal sometimes I can get it up to 2,000 rpm.
I did all the normal stuff distributor cap rotor plugs wires
I have the service manual I suspect out the TPS and the mass air flow sensor I inspected for Boost leaks and vacuum lines my pump is putting out approximately 31 PSI fuel pressure.
I would be extremely grateful if anybody could give me any ideas please and thank you.
I have just ordered a timing light to check timing will not be here until Sunday 3.16.2020
 

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Discussion Starter #8
Just a little update I did yesterday after work.
First I did a compression test I got 180 PSI on all cylinders plus or minus 4 PSI.
Secondly I owned out the whole wire harness and got feedback with an oscilloscope from every sensor besides solenoids. I checked grounds on ECU to engine and body and Battery no more than .004 mv differential. Air flow sensor took in my house and then ohms test on the computer and also found out it is the JDM version I don't know if that's okay on the American computer but the part number is off by 10.
Leak down test came back perfect.
And my new spark plug after 3 minutes of running are so suited up I can't even tell their metal.
I calibrated the TPS sensor. I also remove the distributor all the way up and all the way down honestly it really doesn't make a difference where it is the engine does not change
 

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So I have another update today I spent another 3 hours I checked out the engine harness what the ohms reader I checked out coolant temperature sensor and I wired in the mass airflow sensor on a bench and tested it out heard the service manual and they test good
 

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So I have another update today I spent another 3 hours I checked out the engine harness what the ohms reader I checked out coolant temperature sensor and I wired in the mass airflow sensor on a bench and tested it out heard the service manual and they test good
Did you check the easy stuff like Coil, Ignitor, Wires, Plugs and then the system as a unit? Are there any vacuum leaks past the AFM?
I had a similar problem when I swapped a 6th generation Celica to 3S-GTE. Added a new larger ground from O'reilley's and all problems went away. The stock ground was just too old to keep up and this was a dozen years ago.
 

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I have just ordered a timing light to check timing will not be here until Sunday 3.16.2020
There is no point in discussing this until you have done a timing check. This situation pretty much just screams "timing! timing! Somebody please time me!" I suggest that you check the valve timing also. Even if the ignition is at spec, having one of the cams a tooth off could also cause these symptoms.
 

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Okay guys I understand I will inspect the ignition system her the big green book and I am going to get a timing gun this morning I just got done replacing all the capacitors in the ECU two of them were completely fried and leaking electrolytes
 

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The only reason I didn't check timing right away is because the guy has a huge check list of everything he's done and papers on the condition of the previous pot he replaced I got a stack of paper with all serial numbers of wires and harnesses that he put in the car and he checked off timing belt idler pulley and seals
I am going to get a timing light right now thank you guys for your input much appreciated
 

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Did you check the easy stuff like Coil, Ignitor, Wires, Plugs and then the system as a unit? Are there any vacuum leaks past the AFM?
I had a similar problem when I swapped a 6th generation Celica to 3S-GTE. Added a new larger ground from O'reilley's and all problems went away. The stock ground was just too old to keep up and this was a dozen years ago.
I'm going to O'Reilly's right now I'll install another big ground
 

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There is no point in discussing this until you have done a timing check. This situation pretty much just screams "timing! timing! Somebody please time me!" I suggest that you check the valve timing also. Even if the ignition is at spec, having one of the cams a tooth off could also cause these symptoms.
I am going to have to get the big green book out and see how to do individual timing on the cams without pulling the motor I'm assuming you mean checking the dots with the lines on the cam cover
 

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Guys I just wanted to let you know I did the timing light test I put the jumper in the diagnostic port if it was supposed to read -10 I am probably around somewhere - 30
Btdc
 

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Yikes I'm suprised your compression was so good with timing being that far off. Good thing you found the problem, you could have fixed the timing relatively quickly without removing the engine but I guess it doesn't hurt to check over the PO's previous work. For a more precise alignment (other than the cam gears on the timing cover) you can remove the valve cover and the cams have a dot will line up with marks on the cam caps.
 

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Hi my name is John I just bought my first Toyota car I've ever owned it is a 91 Toyota MR2 with a J spec engine Turbo.
Unfortunately I didn't get to do the swap myself. So I'm jumping into someone's project.
As far as I can tell they did a very good job everything seems to work properly except the engine running.
It takes a lot of cranking to get it to start up and when it does startup it is puttering skipping
And will not rev up at all if I feather the gas pedal sometimes I can get it up to 2,000 rpm.
I did all the normal stuff distributor cap rotor plugs wires
I have the service manual I suspect out the TPS and the mass air flow sensor I inspected for Boost leaks and vacuum lines my pump is putting out approximately 31 PSI fuel pressure.
I would be extremely grateful if anybody could give me any ideas please and thank you.
I have just ordered a timing light to check timing will not be here until Sunday 3.16.2020
Try, Gas tank is dirty, spark plugs, timing.
 
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