matts86fc3s

already looked in FAQ and been a member of nopistons.com for a while and asked all of them already. now i need your guys's help. ok, so if youve read my other posts i still have the 3800 problem and before you ask, yes i grounded everything, and i mean everything from front to back. didnt help at all. so... i checked resistances of the crank angle sensor... good, aws valve...good, bac valve.. good, now heres 3 things i need your help on.

(1) first off, my car was built before nov of 86, and 7's built before then had problems with the ground on the pressure sensor, so i regrounded it just like they did when they had the recall back in the 80's... i have another pressure sensor tho, found it in my parts car. this one and the one on my car look exactly the same except the part numbers are different. old on reads (N327 6612 E1T12071) and the new one i found reads (N350 9227 E1T12272) can i use the new one??????

(2) im using an s5 tps on my s4, i just spliced the wires from the s5 sensor to the s4 plug, and cut the wires on the oil metering sensor i think is what it is. before putting it on i checked it with an ohmeter, no opens or shorts, i went out and checked it just now and it has a big open in it from about halfway all the way to full throttle... and i have an old s4 tps laying around... does the same damn thing as the s5 one...????

(3) my volt gauge reads just a little bit over 12 volts, ide say about 12.3 maybe... shouldnt it be putting out close to 14? or are rx7's just different like that. my buddy has an 86 that reads exactly where mine does and he has no hesitation...

HAILERS

Using a N350 on your 86 is not allowed.

There's no oil metering sensor on a series four car. Period. I'm clueless about what and how you made the series five tps work on your car. I don't disagree that it can be made to happen (narrow range part of the series five tps), but it's vague as to how you did it.

The volts sound low BUT use a digital volt meter on the battery terminals to get a better reading and while your at it, measure the voltage at the alternator output post while your in the area. The voltage is probably much better than what your seeing on the gauge.

I'll look into the part number of the pressure sensor. There is a free, online parts manual on this site. Look for SureShot.

classicauto

iTrader: (3)

^^
I assumed you were getting the reading of 12.3 volts from a multimeter, not the gauge....

touched on a good issue though, if you are getting largely different readings from the alt. post in comparison to your battery, you have something eating up voltage somewhere and this could be causing or related to your hesitation...

HAILERS

If you go to the SEARCH engine on this site and put in E1T12071, you'll get a couple of useless hits. Just FYI

jgrts20

Do Your Actuators Work? Most 3800 rpm hesitation problems are because the ports arent opening right or not opening at all above 3800 rpms.

Its a basic rx7 problem

HAILERS

Look at the 86-88 parts manual (free and online) and you'll see that the non turbo sensor is a N327-18-211.

The series four use FOUR wires to the plug of the sensor. The series five, I think use three. Those don't use the black/white 12dc wire on that plug.

It's easy to figure if the sensor is more or less good. Go to the ECU and backprobe the pin for the boost sensor, pin 2B on series four and with the key to On, engine OFF, see how it shapes up against the figure given in the free, online fsm. Fuel section.

And as a note, on my first series four non turbo, the car had big hesitation when I removed the orifice from the sensors vacuum line. Just a thought.

Orifice can also be looked up in the free online parts manua. Look in the Alphabetical Index. Start with the letter *O*.

The early 86-87 cars had hesitation problems. It was traced to a AFM problem. The cure was to add an extra ground to the boost sensors brown/black wire and to terminate that wire near the neck of the thermostat housing. I've posted that factory service bulletin on this site before. I'm sure it's been deleted so someone can post some crummy shot of some halfass fender flare. See ALLDATA.com for factory service bulletins.

HAILERS

And while we're at it, that 87 non turbo car of mine had hesitation. I did the boost sensor added ground and it did not work. I finally found if I grounded the pin 2R (using memory here), that solved MY problem. Others have done the same and it did not work for them.

And a little bit of venom here: since that car was a non turbo I made it into a turbo. If I remove my extra ground at 2R, the hesitation returns with a vengence. And the last time I looked, my turboii engine did not have auxillary ports. So....mud in your eye.

matts86fc3s

my 5th 6th ports are wired open. im experiencing what seems to be a fuel cut hesitation not just hesitation at 3800. i grounded my pressure sensor brown/black wire and all four of the ecu ground pins. i grounded the fuel pump, battery, tranny, upper intake, and harness ground under intake. so thats not helping. my car did not have the oriface in the boost line so i bought a new one and put one on the line about half way between minifold and sensor, did not help, new fuel pump, filter, plugs, secondary injectors, tried different computer. and the boost sensor although different numbers match up to the plug and everything, (both have 4 spades where a four plug connector hooks up) its the same in every exact way except the numbers. and the series 5 tps is easy to hook up to the s4. you cut the omp sensor wire and dont use them at all (the little sensor closer the throttle body itself so its just there not doing anything becuase i dont need it. then i took the 3 wires from the actual tps sensor of the s5 (same color wires as the s4 just different conector) and spliced them with butt connectors to the old s4 plugs, works good except it has a short/open in it. and yes i mean the alternator guage reads like 12.2 not a voltemeter. is there any other alternator i can get that puts out more volts and taht will bolt in pretty much to stock mounting(cept for the connections wich can be spliced) ?