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chphlds 02-23-2013 11:47 AM

t p i problems
hey guys,
anyone know of a tuned port specialist in the northern mass.,or southern n.h area?

123pugsy 02-23-2013 05:36 PM

Post the problem.

Alot of guys here familiar with fuel injection.

There's not much difference between TPI and any other injection system.

LATECH 02-23-2013 07:46 PM

After re reading through your threads, I realize
1 you have a 86 Tuned port SBC
2 you should have a 16198259 ECM to run it
3 I did not see a Mass Air Flow sensor on the engine or in the airstream.
4 It has become obvious that you could also have god knows what for a wiring harness this could be 1 of 2 of your biggest problems.
I have seen you post several times and realize your head must be spinning.
Do you have any part of the harness that isnt plugged into a sensor or the computer.
Didnt you also say the ECM has 3 plugs and the harness has only 2?
Hmmmmmmm. :pain:

chphlds 02-27-2013 04:28 AM

t p i prblems
the harness has three plugs that are all pluged into the computer.the computer is for speed density[16198262] and it is running has a paneless harness that has wires cut.since the car is in storage,i cant do much work on it now,but this problem is driving me nuts.i keep going to look at it and just scratch my head.have found a hot rod shop close by and as soon as the roads get better,will take it to them and hope they can figure it out.
thanks for all your input.i have learned a lot.

123pugsy 02-27-2013 08:42 AM

According to your pics, it is not running MAF.
You don't have an air intake tube at all. This is where the Mass Air Flow sensor is located.

Just trying to help you understand your engine. Don't take it the wrong way.

As mentioned, if you want to run MAF, you'll need a new ECM, you said yourself that your ECM is speed density (MAP which stands for Manifold Absolute Pressure) and maybe a new harness.

bigdog7373 02-27-2013 11:03 AM


Originally Posted by hcompton (Post 1651151)
TPI blows it does not flow enough air in stock form and the aftermarket solutions are very costly once you get everything purchased and installed. USally wiring harness, upper lower and throttle body need to be replaced along with injectors and computer just to hit 300 hp. then the troubles really start costing money.

Junk the TPI install carb and intake drive car for next 20 years without problems.

This is so obnoxious. The tpi is a decent system.
Op: what is your problem? We can't help you if you don't say what's wrong.
If you're running a cut harness then 99% of the time you have to have the computer tuned. Basically it's looking for signals that it's not getting.

bigdog7373 02-27-2013 11:37 AM

My neighbor had and irocz with the tpi engine. All he did was a cam and exhaust and that thing was definitely no slouch. For the average build it's a good setup and performs well. Plus it's very street friendly especially as a daily driver or such. Now if you were trying to put 500 to the wheels i can see that it will be a problem. But to get 400 crank hp shouldn't be a problem at all. Just like carburetors it will only support so much power. You can run a mild small block on a 600cfm but you'd definitely need to step up to a larger carb if you wanted more power. Same with the tpi. The stock setup can handle moderate power but it needs to be modified to make support higher power levels.
Saying the tpi sucks because it can't handle high hp is like saying tbi sucks for the same reason. Or that 2barrels suck cause they can't make 6million horsepower. Everything has it's purpose and the tpi does exactly what it was designed to do.

chphlds 02-27-2013 11:54 AM

believe me,i don't take any thing the wrong way.i know you guys are trying to help,and I appreciate it.
I want to keep the t p I and am not concerned about speed.just like cruising and cruise nights.i have no preference in running maf or map.which ever will be the less costly.the cars runs fine,once warmed up,so I must be missing something.thanks for all your input.

64nailhead 02-27-2013 04:26 PM


Originally Posted by LATECH (Post 1649893)
After re reading through your threads, I realize
1 you have a 86 Tuned port SBC
2 you should have a 16198259 ECM to run it
3 I did not see a Mass Air Flow sensor on the engine or in the airstream.
4 It has become obvious that you could also have god knows what for a wiring harness this could be 1 of 2 of your biggest problems.
I have seen you post several times and realize your head must be spinning.
Do you have any part of the harness that isnt plugged into a sensor or the computer.
Didnt you also say the ECM has 3 plugs and the harness has only 2?
Hmmmmmmm. :pain:

Agreed. I have to admit that I missed the lack of MAF in the pics, but I'm in agreement that there is a mismatch of parts. OP put in an earlier thread that he has a 9th (cold start) injector and it is hooked up, but there wasn't any MAP systems that utilized the 9th injector.
As I mentioned in another of the OP's threads, getting some O2 datalogging info would be very beneficial as to why his engine runs poorly when cold. Also performing a pinout of his harness and comparing it to to stock pinouts should illuminate whether his harness has been modified.

Hopefully the shop that the car is going to be taken to is capable of doing these things. If so, then I'm sure the problem will be resolved.

Regarding, the 'obnoxious' comment, I don't know if I'd say obnoxious, but I would say close minded and I believe it is relatively egotistical to assume that everyone else wants what you want - to each his own:thumbup:

LATECH 02-27-2013 06:14 PM

X2 with Nailhead. The TPI did what it was designed to do at the time is was built, and did it well.
80s cars lacked any power at all and the way to sell a performance car was to build it to run stop light to stoplight. The TPI works well to build torque and doesnt need to rev high to do it. That would also allow pretty decent mileage if just cruising.
They also look pretty cool , especially in street rods when some of the stuff is polished up.
Not my cup of tea, but I allways enjoy seeing them at the car show.
Helping a fellow hotrodder is important. If you dont like the build ...dont post.
Negativity usually comes from within someone who is unhappy with themself, so they try to make others unhappy , so they arent alone. Pretty sad.:P

gearheadslife 02-28-2013 07:53 AM


Originally Posted by hcompton (Post 1651228)
What part of the tpi is a good system? Mine was junk. Replacement cost was more than it was worth and a carb makes more power with less problems. The tpi does not flow is its most killing problem even with all the best stuff stock manifolds will not make much more than 300 hp no matter what mods are done sep for boosting it.

Now with boost they work ok. great for turbos give good low end tq. But for NA engine that will spin over 6000 rpm then the tpi will not work. They are so small the engine will not make power above 5K rpm some say 4K rpm is the max for the system. My vette came with the best gm had to offer it was still crap.

The simple fact is clear to anyone that has any knowledge of tpi. It is designed to make max power at 2500 rpm. below that is good above that is good. But get to far away and it will clogged your engine worse than running a two barrel carb. Most two barrels will flow more air than the stock tpi system.

Yeah good system but if you want power let it go. get a bigger manifold and tbi or lt1 or edelbrock system or just a nice big carb. all are way better. Carb only cost a few hundred bucks and your back on the road.

you can not get the low end ft lb that a tpi gets..
telling the guy to just install a carb. is somewhat silly.. as you don't know if he has to pass emmissions.. and opening the hood and the tester see'n a carb will be instant fail..
why the tpi wasn't used in trucks.. other than cost..
I'll never know..

123pugsy 02-28-2013 08:46 AM

I'm running a 92 TPI unit in my 4500 lb Chevy pickup and it does have the nice torque.
Mileage has increased since the swap as well and she runs smooth after installing a milder than the mild cam I had. I picked up more torque with that swap and hopefully a bit of mileage as well.

All this talk of wiring harnesses rotting and stuff is making me nervous though. I hope it doesn't turn to dust and fall off my truck.

I have had 2 injectors go on me and that is a pain. The design kind of sucks as the whole upper plenum needs to come off to get the fuel rails out.

I agree with lack of high HP. I have a dyno that shows how it drops off after 4000 RPM's.

For me torque is king though and I love it. :thumbup:

bigdog7373 02-28-2013 08:56 AM


Originally Posted by hcompton (Post 1651151)
TPI blows


Originally Posted by hcompton (Post 1651587)
tpi was bad arse

Lol, you ok dude?

chphlds 02-28-2013 03:24 PM

t p i problems
5 Attachment(s)
hey guys,
thanks to your last posts,i finally realized that i am not running things are starting to make more sense.i then would have to be running map.correct?sorry if i sound like a moron,but this is my first experiance with tuned port.i posted a few more see if you guys can see anything else.the only things that i see unpluged are the knock sensor,which i will hook up befor driving,and the other plug next to can also see a few wires cut to the ecm. any input appreciated.

Soul_Hunter 02-28-2013 04:36 PM

hcompton, there is nothing wrong with TPI, it was a great setup for its time & it still works perfectly fine for a lot of people now, myself included.
a better TPI intake for high horse power/high RPM is NOT anywhere near $5000.00.
no need for a throttle body if you get the right TPI intake.
replacement injector are NOT $400.00 for a full set.
NO system will last for 30 years without repairs, carb or FI.
newer vehicles have many more wiring problems than the older vehicles did at the same time or mileage, and those problems will only increase as the late model vehicles get older.
repairing or replacing a wiring harness isn't a big deal if you know what your doing.

chphlds, i did a quick read thru of your other threads and i'll be repeating some things.

the painless wiring harnesses are pretty good quality, at least everyone i've seen has been.
from the ECM number, your system is a MAP system.
using the MAP TPI system is very popular for swaps into hotrods as it allows for a much cleaner install vs the MAF systems.
the cold start valve, or 9th injector is not needed with MAP.

with a painless harness, you should have the ALDL connector & SES light, find the connector & the light. the light is probably just an orange light mounted next to the ALDL.
if the knock sensor is not programed out of the ECM chip, the ECM will have a code for it & the CEL will be on all the time and the motor will have reduced performance.
the light should come on at key on. if the light works, jumper the ALDL terminals A&B & turn the key to the on postion. the light should flash out any codes. with no problems it should flash code 12. if there are problems, the code 12 will be followed any other stored codes.
its not unusual for the knock sensor to be programed out for an install like you have.
a call to painless wiring may turn up some good info about things such as what the base timing should be & how to check it.

with it running fine once warmed up, it sounds to me like it is going into closed loop & the ECM is controlling fuel.
what is the fuel pressure with it running at idle?
i can't tell from the pictures, but being an aftermarket install you may have an adjustable fuel pressure regulator.

a data log from the ECM could go a long way.
if you have a laptop, you can build or buy the ALDL cable, download the software & do some data logging. TunerPro is a great little program for data logging. using TunerPro with a laptop you get a much longer data log & the update rate is faster than what any of the scanners do.

something i see in one of the pics and don't like, what do you have for a crankcase breather filter? please tell us it does not have a second PCV valve on the other valve cover.

are you on the thirdgen site?
not taking anything away from Hotrodders, but thirdgen truly is the premiere site for TPI systems.

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