eyeoutthere

This is the second installment of the “hooked battery up backwards… car is poop” thread.

This I my current status:

The gauges don’t work but the “add coolant” buzzer keeps coming on despite the fact that there is plenty of coolant in it.

The car won’t idle. I checked many times for vacuum leaks, double checked the AFM connection, tried the Fuel Pump Check Connector jumper thing, made sure the alternator connector was plugged in, and checked a bunch of other stuff.

The car revs good and will stay running if I keep on the gas, but it has a slight misfire.

I started the car and held my foot on the gas to try and get it up to normal operating temp and see if it would idle. I had it running at 3000rpm for about 2 minutes (maybe less) when I noticed the exhaust manifold glowing red :shock: (not the cat, the actual manifold was glowing).

What could cause this?
Could a leaky intake gasket cause enough of a vacuum leak to make the car not idle?
What could cause an exhaust manifold to glow red?

Thanks,
Jason

ForsakenRX7

This is a non-turbo right? This is a shot is the dark, but check that cat. It may be clogged.

eyeoutthere

Non-Turbo.

The clogged cat is a possibility. I have a pretty big exhaust leak at the header flange and a lot of exhaust is coming out there.

The previous owner said the flange (on the exhaust cat side) was warped and that is why it was leaking.

I’ll take the exhaust off tomorrow and see if anything changes.

Any other suggestions?

ForsakenRX7

Its a possibility that the reason that leak is there is because of the clogged exhaust. It has to go somewhere right?

eyeoutthere

That’s what I was implying.

sub9lulu

iTrader: (7)

holy **** i have the same exact problem
the engine gets flooded sometimes too

eyeoutthere

I disconnected the exhaust but the car still will not idle. I didn't mess around with it too much because i didn't want the neighbors to complain.

I am going to try end zero the TPS.

Could that be my problem?

Mr. Gadget

check your compression. Sometimes a blown apex will dump fuel into the exhaust where it WILL ignite.

ilike2eatricers

If it was the TPS I would guess that it is severely misadjusted, not saying its your fault. The coolant buzzer may be because you have air bubbles in your coolant system.

Just to let you know a few weeks ago my car wouldnt idle and I tried the same thing (keeping accelerator pressed until warmed up) but that didnt work and after about 3-5 minutes the cat began to glow. I still think it is a vacuum leak.

Hope you find it.

EDIT: Sorry but forgot to post that it the problem was the AFM was loose. Maybe you have a faulty AFM? Like you shorted it out by the battery connection mixup.

eyeoutthere

Well I was messing around with the TPS adjustment screw but nothing changed. So I am guessing it isn’t that.

It does sound a lot like a vacuum leak, but I can’t find one. I will keep looking.

I was suspecting the AFM as well. I am going to see if I can find someone local who will swap AFMs with me.

I’ll keep you posted

Thanks,
Jason

ilike2eatricers

Do you have a s4 or s5? If its a s4 maybe you have your AFM mounted upside down. If it was upsidedown it would have to fight gravity and yea just a possibility.

MaxRX7

no way me three, I bought an 88 GXL with seized engine and after the ATF treatment. I got it to start but it dies unless I rev it up to 2k+ RPMs

MaxRX7

I forgot to add, I'm thinking it is fuel related. I don't have too much info regarding the history of this car other than it was sitting for 6 months w/o starting.

The fuel is old, so I'm thinking to drain the fuel tank, replace the fuel filter, and check the fuel injectors..

eyeoutthere

hmmm
My fuel was sitting for a while too (possibly 6 months or more, I don't know because I just bought the car). I wonder if that is my problem.

hornbm

WOW me four. Same problem I have, I have to rev it imeadiately after I start it to 2k or it dies.

Dlbgirl

iTrader: (1)

Lots of people with this problem, yet not many proven solutions...I had an 88 SE doing the same thing and after 3 months of tinkering and out of frustration I put in another engine...cranked right up without a problem. It would be nice if that engine sitting on my garage floor is actually OK. Chasing down this idle is a biitch.

eyeoutthere

Update!

I zeroed the TPS (adjusted it to one 1k ohm at idle0. No change

I tested the AFM per the procedure in the FSM. Everything checked out. However, the resistance didn’t seam to change very smoothly as I opened the flap.

Checked the Crank angle sensor. Everything is good there.

I added a ground to the frame (no change)

I measured the voltage between the negative battery post and the engine block (checking for a bad ground). The voltage was about 0.2V while cranking and dropped to <0.1V while running. That seems reasonable.

I was able to keep the car running by holding the flap in the AFM open some, but it ran like ****. (This would still point to a vacuum leak I would assume).

Does any of the above suggest that it may be anything other than a vacuum leak?

If I rigged up a vacuum cleaner to the intake (to suck air through the intake), theoretically I should be able to hear my vacuum leak right? Is it worth a try?

Any other suggestions?

Thanks,
Jason

TahoeTaco

I just bought an 86 GXL yesterday, and it is doing the same thing. I start the car, it revs to about 1500-2000rpm, then it tries to drop down and idle at about 500rpm and just dies. Also i try to give it gas once it revs up to 1500 and it doesnt have any effect, after cranking it a few times and letting it die it will finally let me give it some gas, I hold it at about 2k rpm for a few minutes and once its warm it will idle(pretty rough) but it doesnt die. I can also shut if off and it starts up fine once its warm, but still with the rough idle.

Another thing, im getting the dreaded beeping( ive done the searches on it) the only thing is it is just a constant beep, there isnt a pause after a certain # of beeps like with the guys whose steering sensor was acting up, and it keeps beeping even after I shut the engine off.
Sorry about the long post.

eyeoutthere

Fixed it! (I think)

I took the intake off to see if I missed any lines underneath it. As I was taking it off I noticed one of the intake bolts was loose.

Everything was ok under the intake, but when I put it back together I used RTV on the manifold gasket and made sure all the bolts where tight.

The car started and idled great. I only let it idle for 10sec or so because it was late and my exhaust was disconnected.

I hooked the exhaust back up, filled the tranny with gear oil, and bleed the clutch stuff (all by candle light. No power in Rochester )

I started it again and it only idled for 8sec or so then shut off. But the idle sounded nice and smooth.

I didn’t have any time to play with anything after that.

So that is my status.

-Jason

eyeoutthere

sounds like a vac leak to me.
My coolant buzzer beeps too. But it is a constant beep. It will continue to beep when the ignition is on, regardless of if the engine is running or not.

If it is beeping when the ignition is off, I don’t know what that could be.

TahoeTaco

Thanks, ill check those out.

dr0x

There shouldnt be any power to make the buzzer go off while the ignition is off.

Kenteth

One thing about us rx7 owners... we are definately hardcore. Go buy a Honda...generator... hah, so when the power does go out, you'll be the only guy on the block with power. Talk about envy, power and an rx7!

Kenteth

Better yet, get a cheap belt drive generator and buy some old cheap honda for $50 bucks, pull the engine and trash the car. You've now saved yourself about $800 dollars on a generator. Other good uses for honda engines:
Garage exhaust fan, belt driven of course; air compressor drive (haha, your air compressor has 7hp? mine has 110!); mount the radiator horizontaly, cut the fan off and made a grill... Make a go cart. Use it as your garage air condition drive