Manntis

Pam has started doing something wierd... once she reaches operating temperature, she settles at 800 RPM all well and good - but then I drive her and whenever I stop at a stoplight she pulses between 1000 and 1500 RPM. She revs up to 1500 and immediately drops, repeating about 50 times per minute, almost like an automotive heartbeat.

If I give her throttle at idle, the pulsing continues all through the RPM range e.g. if I put her up to 3,000 rpm she'll pulse to 3,500.

Is it an EGI processor gremlin? A vacuum leak?

brownmound

Have you read any classics lately??

Right on.

MarkPerez

Or maybe an electrical plug. got unpluged somehow.
Maybe check the wiring. what was the last thing you did under the hood, before 'she' started acting up,,also,,maybe fuel filter/injector nozzle(s)
of coarse, i'm guessing now.

abeomid

check your BAC and the vaccum lines that go to it.

RotorMotorDriver

iTrader: (1)

My Dads did that until we changed the 02 sensor, and replaced a couple vacum lines. I dont know which ones though, sorry.

~T.J.

PS - Like the new avator and title?

gump

That sounds like the beginnings of the problem that myself and a few others have been having with their SE's.
Here's the thread info...

https://www.rx7club.com/forum/showth...hreadid=103324

Mine turns out to be a Vent/Vacuum solenoid problem.
Hope this helps.

Manntis

Did you buy the $268 solenoid to fix it?

error402

Hey Mantis, it sucks to hear that Pam is acting up for you. If it make you feel any better I had the same problem with my '85 GSL-SE. My solution was to rip out the entire engine.

...

Well, I guess I should give you the entre story. I bought it with the intention of ripping out the engine(and everything else). It wasn't running when I bought it. So, when I finally got it started and moved to my garage, it was doing the same thing. I just "oh well" and proceeded taking the engine bay apart. I know it doesn't help, I just wanted to share my story. BTW: This is the same '85 GSL-SE that is getting the 20b tt transplant. *cheesy grin*

-Error402

gump

No way! I recently purcahsed used V&V solenoids from a fellow board member who has SE parts. They are at the post office waiting for me. Hopefully I'll get them in tomorrow evening after work. I'd rather take my chances buying used ones at an 1/8th of the cost for new ones. Thats nuts. In the mean time, there is a simple way to test to verify that it's your V&V solenoids. It's explained in the Mitchell manual. If you don't allready have a copy, it's located here.

Mitchell Manual

Pages 240 and 241 specifically. Explains how to test to see if your problem is with the V&V solenoids or the throttle body itself. I did the test and it was the V&V solenoids.

In the mean time you can plug the Vent Solenoid Valve Inlet Port to stop the idle from pulsing up.

Good luck!

Strider

Sorry about your car woes, but dude! People were bagging on you about your picture being creepy, but Pamela? That reminds me of that Stephen King book "Christine".

Damn Manntis, you are creepy

Manntis

Oh come on... you know why she's called Pamela

Suparslinc

Something to do with silicon I guess?

Manntis

Close. Legend has it my car was once that of Pamela Sue Anderson

White84SE

My old '84 SE did this for awhile when I had it. I committed the ultimate sin and adjusted the throttle position sensor before checking anything else. Cured the symptoms for me. Car did as you describe, and it also was EXTREMELY jerky at low RPMs. As in, enough to give you whiplash. LOL Anyways, the tool the FSM tells you to get can be easily replicated from Radio Shack for under $7 'Merican. There's a website somewhere out there that tells you the exact part numbers you need.

--Danny

Manntis

Okay, there's the vacuum solenoid & electric motor assembly on the left (driver's side, in North America) side of the dynamic effect chamber. This gizmo/collection of gizmos has a rubber hose running to the DEC, with a 90 degree bend in it. When I pinch the hose, the surging stops.

So: is it the vacuum solenoid, or the electric gizmo? Are these things/one of these things there for emissions purposes?

gump

Ok, I attached a picture to this message. Is this the hose you are pinching? If so. Then this picture shows how you can plug the hose any way possible to get it to stop. In my case. It would stop when I pinched the hose, but 9 out of 10 times it would start back up when I let it go.

Moving on... Did you read the pages in that Mitchell Manual I mentioned? In the picture I attached, the solenoid I am talking about sits right next to the green and orange connectors. See them? They are barrell shaped. Well on the one next to the orange plug, if you remove the vacuum hose from the top of the solenoid (can't see it in the picture, it's underneath the BAC), and you place your finger on the port you just pulled the hose off of, the pulsing should stop. If it does, apparently that means your solenoid is shot. I still have not received mine because the post office is open onlyl while I'm working, so I can't verify this...yet.

Is this making sense?
Matt.

ok, forget the picture, it won't let me attach it because the picture is allready on the forum thread I mentioned earlier here...

Forum Thread on the pulsing problem.

Manntis

So if pinching the hose helps, it's the barrel shaped solenoid below, not the bronze vacuum solenoid on the same part as the hose?

jeremy

iTrader: (1)

put a cloths pin on it and be done

Manntis

I prefer having all parts functioning as they're supposed to, or replacing them with better parts.

Suparslinc

According to my grandpappy, lgend has it that my car made a guest appearance in the movie Die Hard

Manntis

Mine belonged to her for a year or two before she was famous, and since she's famous mainly for two things (the left one & the right one) it ain't much to brag about, ut there it is; the reason my car is named Pam

gump

I'm not sure about that. But if you remove the vacuum hose from the top of the vent solenoid and plug the port with your finger and the idle smooths out, then you need the solenoid. I replaced my solenoids and so far the results are great. I posted a picture of the solenoids in the link below which covers this problem.
Good luck.


Thread with solenoid pic.

Manntis

I hope replacing the solenoid solves it - today she wouldn't go below 3,000 RPMs and I had to brake without a foot on the throttle to stay under 50 KPH.

zookeeper

Manntis: I hope it does too! I've had the same prob with my '84 SE for awhile now. I was convinced it was the TPS 'cause I could dup it by slightly depressing the TPS button. It wud also act up the same way if I got the TPS wet. Anyway, I R+R'd and adjusted the TPS... Voila! No more surging! THEN, after reading all these posts and the Mitchel Manual - I decided it would be a good idea to, like, totally lube all the throttle linkage. Ya know? So I douched it liberally with WD-40. Sum-beach if the problem didn't come back again! Go figure!

Attempting to rotate the secondary throttle valve lever counter-clockwise (per Mitchell Manual pg 240) did not help. I've yet to try the "finger on the vent solenoid valve" trick 'cause the vac line is a little hard to get at and the engine was, like, a little too hot for me to be sticking my fingers in there at the time.

Good luck with yours, and let us know if you solve it.

BTW, I posted a couple pix of my '84 on the "Let's see your cars..." thread. Let me know what you think of it.

LongDuck

Same problem - cleaned out throttle body and lubed axle shafts for primary and secondary valves in the body, and now have surging.

You can't win with this car, I tell you.

will be trying the Vent Solenoid check tonight to see if that fixes it - then will block the BCAV airpipe to see if THAT fixes it, then will replace all vacuum lines under the intake manifold and see if THAT fixes it...!

Sheesh...