'91 Beretta Woes

Have a flashing light? Gauges acting funny? Bad idle? Get your problems solved...
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'91 Beretta Woes

Postby Krstna » Sun May 17, 2015 7:17 pm

Ok, so my beretta was having problems with power loss on acceleration, rough idle when warm, and wouldn't go past 3000 rpms sometimes. I ended up taking her into Midas for an under the hood inspection and was told 4 of the 6 injectors were bad and should replace all of them. Here's a pic of my actual receipt. Idk what under the hood means to other people but when they told me under the hood inspection I assumed they would actually be inspecting things....
as you can see I stupidly paid them $100 to hook her up to a scanner thing.

Anyways, I went ahead and replaced the plug wires and had my moms boyfriend, not a mechanic, replace the injectors. (I helped!!) Problem solved until I drove long enough for the engine to warm up and then same thing. Possible causes:

1. The injectors were from pick and pull and could also be bad. We later, not before like smart people might do, tested the injectors with an ohm meter and the all tested at 12 ohms. That means they're good right? Maybe just dirty?
2. Nothing was torqued when put back together. My boyfriend later torqued the intake manifold and stuff and that actually seemed to help a bit but something still felt off. Like something was getting stuck somewhere or clogged, idk.

So being the genius that I am I figured the egr and the things listed on the receipt that they didn't do probably just needed to be cleaned. My boyfriend and me went to pep boys and got all the different types of cleaner that would be needed and after a small disagreement I left him to do all the work. We don't work well together on cars, lol. well he tells me she's fixed but I drive her and she's driving a different kind of bad. Here's what he did:

1. Cleaned the Pcv valve/hose with some spray
2. Cleaned the throttle body
-he sprayed stuff into the throttle body while the engine wasn't running. I've read that is BAD?
3. Cleaned the egr thing
4. Attached the maf to the back of the engine, where it's supposed to be I think. It was just hanging around before.
5. Torqued it all to spec

That was 2 days ago. She drove awesome til today when she started having all the problems she initially had and then some. Right now my car is just parked on a side road about 5 minutes from my house where she stalled out. She'll start back up and idle fine but when I put her in gears he stalls. I tried to give it some gas when putting her in drive, still stalls.

Could it because the boyfriend sprayed crap into the throttle body? Or maybe the maf is getting hot? I've read it could be the fuel filter, the iac, the tps....

Im pretty sure it's something we did tho. I just don't know. Any advice?

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Re: '91 Beretta Woes

Postby SuperLbody » Mon May 18, 2015 1:00 am

Haha, where to begin? Yes spraying cleaner down the intake while running is very bad but not a death blow. Next time remove the throttle body and clean it. You shouldn't have a MAF on your year 3.1L V6. Could you get a pic of this supposed MAF? With all the issues present, it'll be hard to narrow down just what exactly is wrong.

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Re: '91 Beretta Woes

Postby ronaconda » Mon May 18, 2015 10:40 am

Is there a check engine light when running??? If there is, pulling the code(s) is a fantastic place to start and will usually direct you to the problem. Mine used to do this and it turned out to be a bad knock sensor circuit.

12-13 ohms for the injectors mean they are good.

Start with the typical maintenance parts - do a tune up if one hasn't been done in a while and make sure to replace the fuel filter. IAC valve typically will cause idle issues, not running issues

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Re: '91 Beretta Woes

Postby Money pit Beretta » Mon May 18, 2015 10:48 am

Does it die right as you put it into gear and hit the gas? That is a transmission problem. Another thing you could try is to unplug the TCC(controls the lock up on the converter and tends to fail on the THM125).
Right now I'd say replace the fuel filter.
Does it smell rich?

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Re: '91 Beretta Woes

Postby Asylum » Mon May 18, 2015 11:08 am

I agree with Money.

Try unplugging the TCC solenoid.

It's the square plug on the front of the trans down below the throttle body.

No bad can happen, and you may well solve at least part of your problem



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Re: '91 Beretta Woes

Postby Rettax3 » Sun Jun 07, 2015 9:47 pm

This has been a while. Any new developments? I tend to lean towards fuel issues on this -weak pump not supplying the engine with enough pressure to keep it running once shifted into gear and the load changes. Do a fuel pressure test, make sure everything is to spec to rule that half out. Use the 'loan-a-tool' program at your nearest AutoZone or O'Reilly's to test the system without spending any money on it.

Pretty sure the "maf" you are looking at is the "MAP" sensor -same basic job so far as helping the computer measure the air in the engine to let it match up the right amount of fuel, but it does it in a completely different way. Make sure the vacuum line to it is in good condition and didn't crack when you moved it.

Spraying a little bit of cleaner into the throttle while not running won't hurt anything -a lot can though, but not the symptoms you are describing. Bottom line though is that it is YOUR car, so your rules, right?

FWIW, good Ohm readings on the injectors does NOT mean they aren't clogged or stuck, just that the coil inside them is still good. You would have to flow-test them to be certain that they are good. What car or engine donated the 'new' injectors? Was it a 2.8 or 3.1 MPFI (like yours), or was it a 3100 SFI engine? Those are different injectors...

On your year car, you can pull the codes yourself by plugging a paper-clip into the two ADJACENT ports in the diagnostic link connector (under the dash above the pedals) that have electrical connectors in them (not empty holes). Turn the ignition key all the way on without starting the engine, and watch the check engine light flash 1,2 ="twelve" which means diagnostic mode (sometimes the fan will come on too). It will flash "twelve" at you three times before flashing other codes. Record them, and use a service manual or internet search to determine what the computer is telling you the problem is.

Hope you fix(ed) it! Good luck.

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Re: '91 Beretta Woes

Postby Money pit Beretta » Mon Jun 08, 2015 9:50 pm

After all the time that has passed I have to ask: has anything been done? FB support or something?

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Re: '91 Beretta Woes

Postby Rosz » Thu Jul 02, 2015 11:14 am

Carbon in your egr valve is blocking the seats.... fix your problem by scraping the carbon that is below the seat valve or it is stuck staying on open by a solonoid staying on but most likely carbon on the or around the seat and seat valve there is three holes that must be closed to prevent exhaust from entering the intalke at the right time.

hope this solves it,

Rosz,Certified trans tech.nanaimo B.C.

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