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Discussion Starter #1
Okay, so after having the car for about a week, I realized it really didn't have any power. At all. That was back in April. I have a 91 Daytona, 2.5L Turbo motor. When I put my foot down in 1st or 2nd, the car would shake pretty violently, was far from putting my head back in my seat, etc. It was pretty bad. Along with that, the boost gauge was only registering about 2.5 psi, although I could sometimes get it to go above 2.5, but that was only after I replaced the fuel filter in the back and ran it on 91 octane, I've been running it on 87 the whole time I've had it with one exception. Even free reving the engine in neutral in place, as far as I remember, never being able to get it over about 4 psi on the guage.

Anyway, my dad and I after some tooling and looking around, figured the motor was probably not timed correctly, and after checking everything up, we figured out the cam was one tooth counterclockwise off. We corrected that problem tonight, and now when I free rev the motor it easily goes over 5, I got it over 7 too. When I drove it, it felt like it was faster, more confident and less likely to stall. But while driving, it would not go above 5 psi of boost, even in 1st gear and flooring it, and then it would continue to drop down to around 2.5 psi slowly from there, with continued throttle being held pretty far down.

So it's running better now, but my question is what is going on with my motor? Is it not boosting up to 7 psi because I am only running 87 octane and the knock sensor is keeping it from boosting any higher than that? Or is there something wrong with my wastegate or computers? I talked to my friend who knows a bit about turbos, and he said it might be my wastegate is stuck open or is sticky and not opening like it should. Could this also be an issue with my vehicle? Thanks in advance. Oh, and I also adjusted the distributor, which was really advanced since the time I got the car, probably to compensate for it being a tooth off. I think I have it about right, but I'm not sure.
 

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First things first, check for codes.

Second thing, double check your cam timing. It doesn't hurt to double check. The proper procedure can be found here:
http://minimopar.net/enginetiming.html
Also use premium gas, the engine could be knocking the computer could be pulling back boost. Max boost for this engine is 11 PSI.
 

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Vacuum hoses can also be a problem, old, hardened ones tend to bleed off the vacuum which I know does control some of the turbo functions. When was the last time the whole engine was completely tuned up with air filter, plugs, wires, distributor cap, rotor, and the gap checked? PCV and vacuum lines are the other items to check, along with movement of the turbo components to make sure they are moving.
 

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Discussion Starter #4
dana44 said:
Vacuum hoses can also be a problem, old, hardened ones tend to bleed off the vacuum which I know does control some of the turbo functions. When was the last time the whole engine was completely tuned up with air filter, plugs, wires, distributor cap, rotor, and the gap checked? PCV and vacuum lines are the other items to check, along with movement of the turbo components to make sure they are moving.
Only had the car since May, a lot of the lines look factory, but some are replaced. The engine was rebulit about 5000 miles before I got the car. Spark plugs and wires were replaced somewhat recently, that is obvious. Distributor cap and rotor, who knows, but I'm sure they were replaced as well with the rebuild. Air filter is a reusable K&N, I cleaned it out, re-oiled it, put back in. Air cleaner box and the hoses and stuff look like they are replaced, they look too new to be factory, but maybe they are. Replaced one vacuum hose that looked sucked shut, that helped slightly before I got the timing back on track.

I did check the codes back when I hadn't yet adjusted the timing, all I had were electrical system issues. I recharged the battery and all the codes disappeared, so they were all due to low battery. I will check again though.

Thankfully my dad worked on these when he was still a Chrysler tech, so these engines are kinda his thing, but the turbos he has no idea about, he never messed with anything related to the turbos, but we have no idea if the lines are set up correctly.

Spark plugs are pretty grey-white, which with how advanced the distributor used to be, I am in no way shocked. But they are still in good shape, shouldn't need replaced for awhile yet. I think I'll just wait until I get the car moving with a full tank of 91 in it and see if it goes up to 7 psi or so. And is it really 11 max psi for a 91 Turbo 1 motor?
 

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These engines are NOT V8 torque monsters. You should produce about 7psi boost and be able to hold it for a little while. However should you try to boost more than that on a T1 setup the wastegate opens and it bleeds off the boost so, you're limited to the 7psi on a T1 setup.

It is possible to increase the boost manually by changing the setup but that will put you at risk for burning lean. This condition would be a major risk since burning lean tends to put holes in the tops of pistons and make the engine go boom.

Start with the basics.

Be sure the battery is fully changed. These setups don't like 'low voltage' as they are computer controlled.
Check codes and handle any issues - check all vacuum lines and electrical connections/wires
Be sure the fuel filter is not too clogged.
Drive it like you love it.
 

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check and make sure you have all the orafices (spelling?) in the vaccume lines.
I found some missing on my last daytona and that made a big power boost.
 

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11 PSI is the max boost on his engine Bob. This is a Hi Torque model.
 

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I would guess it is a vacuum / wastegate / air solenoid issue as when the air solenoid is stuck closed it will give only 5 PSI boost. If the vacuum line is connected directly to the wastegate it will also give only give 5 PSI. I wrote this "2.2 / 2.5 Liter Engine Turbo Bleeds" 12 + years ago as I needed to know how the stock boost controlling system worked and how a "G-Valve" worked before doing the modification. I suggest going with the G-Valve setup for less lag. But please understand how it works first, get a "real" boost gauge, and air/fuel ratio gauge before playing with a G-Valve and know how to adjust it. Especially if using a cut-off riser.

http://www.allpar.com/eek/turbobleeds.html

2.2 / 2.5 Liter Engine Turbo Bleeds

Stock Solenoid Bleed

The stock wastegate control system uses the air solenoid to create a bleed. The air solenoid opens and closes real fast at different rates (duty cycles) to create more and less bleed on the wastgate. The more the air solenoid is open, the more it bleeds, and the less the wastgate is open, allowing more boost. If the air solenoid is open less, the wastgate will see more air pressure, and be further opened, allowing less boost. The air solenoid is controlled by the computer by feedback it gets from the MAP sensor. If the air solenoid is stuck closed not allowing a bleed, or if you connect the vacuum line directly to the wastgate, the boost level should be about 5 PSI max. So if you only get 5 PSI your solenoid is likely shot or your vacuum connections are not correct.

G-Valve

A G-Valve does not let air escape but holds it back from the wastegate until a certain pressure is obtained. Then the valve opens allowing the air pressure to open the wastegate. There is a bleed which is not the major controlling factor on the wastegate side of the G-Valve that allows for the wastgate to close again after the pressure closes the G-Valve. If this very small bleed was not on the wastgate side, the wastegate would remain open and you could boost no more than 5 PSI.

The stock solenoid bleed always puts some pressure on the wastgate allowing it to open a little at low boost. This is what I beleive causes some of the turbo lag. A G-Valve does not let the wastegate open at all until is sees the set pressure so it has less lag.

Note: Much of this comes from the work of Gus Mahon (RIP)
http://www.gusmahon.org/html/boostcontrol.htm
 

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First of all, you won't get any appreciable boost while revving with no load. So look at boost only with the load of driving the car. And I don't believe the computer, which does control the wastegate, will allow full boost under all conditions, on 87 octane. 87 is minimum, 91 is recommended, and it does make a difference, especially in summer. Run 91 octane and see what you get.

Finally, re-check ignition timing. It should be 12 degrees BTDC while the coolant temp sensor is unplugged. You can't set the timing without unplugging the sensor. Make sure to plug it back in when done.
 

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DCTZ hit the nail on the head. You know your system is working from the results you've gotten under the different circumstances, but it's not working well. You probably don't have a vacuum line leak because in fact that would would be a boost pressure leak, if you were leaking boost pressure your actuator would be staying closed and you would be overboosting.

I'd start with squirting a little WD-40 in the line leading to the solenoid, when the car hits positive pressure it will blow into the solenoid and out the vent, with any luck that will lube it up and get it moving freely. You may need to try that more than once. NO SOLVENTS in the solenoid, I made that mistake, WD-40 only and blow it out with compressed air if you wish, or maybe the compressed air cans for cleaning your computer.
 

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bamman said:
11 PSI is the max boost on his engine Bob. This is a Hi Torque model.
Torque isn't boost. The torque comes from the stroke of the crank/piston assembly. I thought that all T1 engines limited boost to 7psi.
 

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Discussion Starter #12
Bob ONeill said:
Torque isn't boost. The torque comes from the stroke of the crank/piston assembly. I thought that all T1 engines limited boost to 7psi.
It may be limited to 7, but he might be right too, I'm not sure.
This is from the Allpar 2.2/2.5 Turbo page.

"The wastegate control strategy was revised, providing initial boost at a lower speed, and more boost at medium and high speeds. The engine had 150 horsepower at 4,800 rpm, with 180 lb-ft of torque (measured on premium gas). Boost calibration changes in 1991 added 2 horsepower and a full 30 lb-ft of torque, so the motor produced 152 horsepower and 211 lb-ft of torque at the same speeds."

I'm not entirely sure what that means if I'm honest.
 

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Bob ONeill said:
Torque isn't boost. The torque comes from the stroke of the crank/piston assembly. I thought that all T1 engines limited boost to 7psi.
No, no, no. What I'm saying is that in 1991 after Dodge dropped the T2 and T4, Dodge released the "High Torque" T1 models instead. They made the A-568 standard for some turbo models and upped the boost to 11 PSI to make up for the apparent lack of performance engines. The OP car should be able to boost to 11 PSI is what I'm saying.
 

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Discussion Starter #15
Okay, I haven't had it up too high in the rev range yet since the timing adjustment (since I'm only running 87), but I did manage to pull off above 5 psi today, looks like it got to or close to 7. Figured it might as well get new plugs, got some Champions and put them in. Got some Sylvania ultra halogen sealed beams, or whatever the mark on them is, but the step up from regular halogen. Just waiting for the sun to go down, and I'm going to go fill it up with 92 octane and see what she does from there. Maybe I'm all good for now.
 

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Also make sure your exhaust system is good. A plugged up Cat can cause a lot of problems with it not boosting right.

If I remember right, Turbo I's ran max boost of 9 psi except 1984 cars which I believe was around 7.2psi. Turbo II cars were 12psi.
 

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Discussion Starter #17
1991spirites said:
Also make sure your exhaust system is good. A plugged up Cat can cause a lot of problems with it not boosting right.
Well, funny story about my exhaust...I'll have to take pictures and upload them. I don't know what they were thinking (whoever put it on) but do I ever want it off...

And after driving it, I have to say the new headlamps really did a major improvement on my lighting. I used to be in the dark, for lack of a better term. Now it's as good, if not better, than the amount of light I get out of my Sebring. I feel my Sebring is in need of new bulbs after I finish repairing it's headlights.

Got 92 octane near my place and I still had just above the gas light of 87 left in the tank. It pulled harder, but not that noticeably so, but it's really cool tonight here. I have no idea what I had my engine turning (tach works intermittently), but it was rather high, and it read 10 psi and it kept steady for a few seconds before I backed off. I might have been able to get it higher...but I don't think I want to, especially without knowing even relatively how many revs I have it at. I haven't really had it accelerate at low speeds (like pulling out), but at low speeds it feels a bit gutless still and doesn't feel like it's spinning the tires sort of power.
 

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Bob ONeill said:
OK then I will stay with curtain one..... vac leak somewhere.
A vac leak would give more boost because it would bleed off the pressure to the wastegate so more pressure would be needed to open it controlling the boost. This also happens if the air solenoid is stuck in the open position.

So I go with curtain #2 - the air solenoid is likely shot and stuck in the closed position allowing all the pressure, when boosting, in the vacuum line to open the wastegate at low boost levels (5 PSI).
 

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Discussion Starter #19
Update: Was driving it today, and it has an aftermarket temp gauge in it, on the A pillar, along with a fuel/air mixture gauge (the latter is not hooked up). Anyway, normally the gauge reads around 210, or on 210, no matter what. Well, after about a mile or 2 of driving it on the highway after some more than normal places I stop, the gauge shot up to over 250 by that gauge. Brought it home, looked like the coolant was low, so refilled it to the max level. Adjusted the timing again, using the method above (or attempting, I'll have to get it to 12 later and use a timing gun to make sure). Anyway, adjusted the timing, first run out, had retarted it too much, ran with less power than it did before the cam timing adjustment, but still boosted fine. Right back home, adjusted the timing again, and it ran the best I have ever seen it. Didn't get to pay much attention to the boost though, overheating forced me back home after another short trip up the road. Drove it carefully, ran the AC so the fan was blowing full blast, it only got up to 230 this time, but still. Done for tonight, think I'm going to change the thermostat and the coolant lines, they feel a bit gummy.
 

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Overheating? Bad timing settings? Both bad and indicate to me that there might be something going on here.

In addition to an overly lean condition timing which is set wrong can also contribute to burning the tops of pistons if conditions are right. But more likely than that it tends to help in the destruction of head gaskets as in the timing causes the 'fire' to come too soon and this is not good.

So, with the temp going way WAY too high and you having to reset timing tells me that there may be something wrong now with the inside of the engine. Did you use a good timing light to set the timing?

For example, too hot and losing coolant may mean bad head gasket or cracked head.
 
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